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Mobile devices & hardware

Mobile device types and form factors

Expect questions on laptops, tablets, smartphones and wearables, plus the ports and connectors that link them.

  • USB-C is now the dominant charging/data connector; it is reversible and supports USB Power Delivery (USB PD) up to 240W on the newest spec.
  • Lightning is Apple-only on older iPhones; newer iPhone models moved to USB-C.
  • Bluetooth pairing steps: enable Bluetooth, set device to discoverable, locate device on host, initiate pairing, confirm passcode if prompted, test connection.

Laptop hardware and disassembly

  • Always consult the manufacturer's service manual before opening a laptop - screw sizes and placements vary by model.
  • Use an anti-static strap or mat, and organise screws (a labelled tray or taped-down layout) since laptop screws are rarely interchangeable.
  • Common field-replaceable parts: RAM, storage (SSD/HDD), battery, keyboard, screen and Wi-Fi card. CPUs are usually soldered on modern laptops.
  • Laptop RAM uses SO-DIMM modules (smaller than desktop DIMMs); check DDR generation compatibility (DDR4 vs DDR5 are not interchangeable).

Mobile storage and expansion

  • microSD cards are the common removable storage for phones/tablets that still support it; common capacities use SDHC (up to 32GB) and SDXC (up to 2TB) standards.
  • NVMe M.2 SSDs are increasingly used in thin laptops instead of 2.5-inch SATA drives - check the key notch (M or B+M) matches the slot.

Mobile connectivity

  • Wi-Fi standards: 802.11ac (Wi-Fi 5) uses 5GHz only; 802.11ax (Wi-Fi 6/6E) adds better efficiency and 6E opens the 6GHz band.
  • Cellular generations: 4G LTE and 5G are current exam-relevant standards; 5G offers higher speed and lower latency.
  • NFC (Near Field Communication) is used for contactless payment and quick pairing, with a very short range (a few centimetres).

Mobile accessories and features

  • Know accessories: docking stations, port replicators, trackpads/pointing sticks, styluses (with digitisers), and biometric readers (fingerprint, facial recognition).
  • Mobile device features to recognise: GPS, accelerometer, gyroscope, and IR blasters (for remote-control apps).

Common exam mistakes

  • Do not confuse a docking station (full port replication, often proprietary) with a simple port replicator (fewer ports, less capability).
  • Do not assume all laptop batteries are user-removable - many modern ultrabooks have batteries glued/screwed internally, needing extra care.
  • Remember ESD precautions apply to mobile device repair just as much as desktop PCs - static can silently damage components even without a visible spark.
  • USB-C supports USB Power Delivery (USB PD) up to 240W under the latest spec.
  • SO-DIMM is the RAM module form factor used in laptops, smaller than desktop DIMMs.
  • DDR4 and DDR5 RAM are not physically or electrically interchangeable.
  • SDHC cards max out at 32GB; SDXC cards scale up to 2TB.
  • 802.11ac (Wi-Fi 5) operates only on the 5GHz band.
  • 802.11ax (Wi-Fi 6E) is the first standard to open the 6GHz band.
  • NFC has an effective range of only a few centimetres, used for payments and quick pairing.
  • Most modern laptop CPUs are soldered to the motherboard, not socketed or field-replaceable.
  • A docking station provides full port replication; a port replicator offers a reduced feature set.
  • Always check the manufacturer's service manual before disassembling a laptop - screw layouts differ by model.
  • ESD (anti-static) precautions are required for mobile device repair, not just desktop builds.
  • Newer iPhone models have moved from Lightning to USB-C connectors.
What is the maximum power delivery of USB-C under USB PD?
Up to 240W under the latest USB Power Delivery spec.
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What RAM module form factor is used in laptops?
SO-DIMM (smaller than desktop DIMM modules).
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Can DDR4 and DDR5 RAM modules be swapped in the same slot?
No - they are not physically or electrically compatible.
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What is the maximum capacity of an SDHC card?
32GB.
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What is the maximum capacity of an SDXC card?
Up to 2TB.
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Which frequency band does 802.11ac (Wi-Fi 5) use?
5GHz only.
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What new frequency band does Wi-Fi 6E open up?
The 6GHz band.
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What is the typical range of NFC?
A few centimetres - used for contactless payment and quick device pairing.
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Are modern laptop CPUs typically field-replaceable?
No - most are soldered directly to the motherboard.
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What is the difference between a docking station and a port replicator?
A docking station gives full port replication and extra features; a port replicator offers a reduced set of ports.
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What should you check before disassembling any laptop?
The manufacturer's service manual - screw sizes and placements vary by model.
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What precaution applies to mobile device repair as much as desktop PC repair?
ESD (electrostatic discharge) precautions, such as an anti-static strap or mat.
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What connector have newer iPhone models switched to from Lightning?
USB-C.
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What technology in a stylus allows precise input on a mobile screen?
A digitiser.
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Name two motion-sensing features common in mobile devices.
Accelerometer and gyroscope.
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Networking & connectivity

Networking and connectivity

Networking questions on Core 2 (and touched in Core 1) cover cabling, wireless standards, IP addressing, ports and troubleshooting tools. Know the numbers cold.

Cabling and connectors

  • Cat5e supports up to 1Gbps (1000BASE-T) over 100 metres.
  • Cat6 supports 1Gbps over 100m or 10Gbps over a shorter 55m run.
  • Cat6a supports 10Gbps over the full 100m, thanks to better shielding against crosstalk.
  • Fibre comes in single-mode (long distance, laser, yellow jacket) and multi-mode (shorter runs, LED/VCSEL, orange or aqua jacket).
  • RJ45 is the standard connector for twisted-pair Ethernet; RJ11 is for telephone lines - do not mix them up.

Wireless standards

  • 802.11ac (Wi-Fi 5) runs on 5GHz only.
  • 802.11ax (Wi-Fi 6) runs on both 2.4GHz and 5GHz, and Wi-Fi 6E extends into the 6GHz band.
  • 2.4GHz has longer range but more interference and fewer non-overlapping channels (1, 6, 11 in most regions).
  • 5GHz has shorter range but much less interference and far more channels.

IP addressing

  • IPv4 addresses are 32-bit, written as four octets, e.g. 192.168.1.1.
  • Private IPv4 ranges: 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 - these never route on the public internet.
  • APIPA addresses sit in 169.254.0.0/16 and mean the device could not reach a DHCP server.
  • IPv6 addresses are 128-bit, written in hexadecimal, e.g. fe80::1.
  • Default subnet masks: Class A 255.0.0.0, Class B 255.255.0.0, Class C 255.255.255.0.

Key ports to memorise

  • FTP uses 20 and 21, SSH uses 22, Telnet uses 23.
  • SMTP uses 25, DNS uses 53, DHCP uses 67 and 68.
  • HTTP uses 80, POP3 uses 110, IMAP uses 143.
  • HTTPS uses 443, RDP uses 3389.

Common mistakes

  • Confusing Cat6 and Cat6a distance limits - remember 6a is the one that hits full 100m at 10Gbps.
  • Mixing up DNS (name resolution) with DHCP (address assignment) - a DNS failure still lets you ping by IP, a DHCP failure means no address at all.
  • Forgetting that a default gateway is needed to leave the local subnet, even if the IP and mask are correct.
  • Assuming a firewall block always shows as 'connection refused' - a dropped packet just times out silently instead.

Troubleshooting tools

  • ipconfig/ifconfig shows current IP configuration.
  • ping tests basic reachability, tracert/traceroute shows the hop-by-hop path.
  • nslookup checks DNS resolution directly against a specified server.
  • Cat6a supports 10Gbps over the full 100 metres; standard Cat6 only manages 10Gbps up to 55 metres.
  • 802.11ac (Wi-Fi 5) is 5GHz only, while 802.11ax (Wi-Fi 6) works on both 2.4GHz and 5GHz.
  • Private IPv4 ranges are 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16 - none of these route publicly.
  • APIPA addresses fall in the 169.254.0.0/16 range and signal a failed DHCP request.
  • HTTPS runs on port 443, HTTP on port 80, and RDP on port 3389.
  • DNS uses port 53; DHCP uses ports 67 (server) and 68 (client).
  • SSH uses port 22, Telnet uses port 23 - always prefer SSH since Telnet sends data in plain text.
  • IPv4 addresses are 32-bit; IPv6 addresses are 128-bit and written in hexadecimal.
  • 2.4GHz Wi-Fi has only three non-overlapping channels in most regions: 1, 6 and 11.
  • A default gateway is required to reach any device outside the local subnet.
  • RJ45 connects Ethernet twisted-pair cable; RJ11 connects telephone lines - they are not interchangeable.
  • Single-mode fibre suits long-distance runs using laser light; multi-mode fibre suits shorter runs using LED or VCSEL light.
What is the maximum distance for Cat6a to achieve 10Gbps?
100 metres, thanks to improved shielding against crosstalk.
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What frequency bands does 802.11ax (Wi-Fi 6) support?
Both 2.4GHz and 5GHz (Wi-Fi 6E adds 6GHz).
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Name the three private IPv4 address ranges.
10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16.
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What does an APIPA address (169.254.x.x) tell you?
The device failed to get an address from a DHCP server and self-assigned one instead.
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Which port does HTTPS use?
Port 443.
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Which ports does DHCP use?
Port 67 for the server, port 68 for the client.
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Which port does SSH use, and why prefer it over Telnet?
Port 22; SSH encrypts traffic while Telnet (port 23) sends it in plain text.
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How many bits make up an IPv4 address versus an IPv6 address?
IPv4 is 32-bit; IPv6 is 128-bit.
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How many non-overlapping channels does 2.4GHz Wi-Fi typically offer?
Three - channels 1, 6 and 11.
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What is the role of the default gateway?
It routes traffic from the local subnet out to other networks, including the internet.
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What connector is used for Ethernet twisted-pair cable, and what is commonly confused with it?
RJ45 is used for Ethernet; it is often confused with the smaller RJ11 used for telephone lines.
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What is the key difference between single-mode and multi-mode fibre?
Single-mode uses laser light for long-distance runs; multi-mode uses LED/VCSEL light for shorter runs.
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Which command shows the hop-by-hop path to a destination?
tracert (Windows) or traceroute (Linux/macOS).
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Which command checks DNS resolution against a specific server?
nslookup.
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What is the default subnet mask for a Class C network?
255.255.255.0.
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Operating systems (Windows, macOS, Linux)

Operating systems overview

A+ Core 2 tests Windows, macOS and Linux side by side. You need to know editions, file systems, command-line tools and how each OS handles users, updates and troubleshooting.

Windows editions and limits

  • Windows 10/11 comes in Home, Pro, Pro for Workstations and Enterprise editions.
  • Home cannot join a domain or use BitLocker or Group Policy Editor (gpedit.msc) — Pro and above can.
  • Windows 11 minimum requirements: 4GB RAM, 64GB storage, TPM 2.0, UEFI with Secure Boot, 1GHz 2-core 64-bit CPU.
  • Upgrade paths: in-place upgrade keeps files, settings and apps; clean install wipes the drive.

File systems

  • NTFS is the standard Windows file system: supports permissions, encryption (EFS), compression and journaling.
  • exFAT suits USB flash drives and large files across OSes — no permissions, no journaling.
  • FAT32 has a 4GB single file size limit and 32GB volume limit in Windows format tools.
  • macOS uses APFS by default since 10.13; Linux commonly uses ext4.

Command-line essentials

  • Windows: ipconfig, ping, sfc /scannow (repairs system files), chkdsk (checks disk errors), diskpart (partition management), gpupdate /force (reapplies policy), robocopy (robust file copy).
  • macOS Terminal: ifconfig or networksetup, sudo for elevated commands, apt is NOT macOS — that is Linux.
  • Linux: ls, pwd, chmod (permissions: rwx for owner/group/other), chown (change owner), sudo (elevated privilege), apt/yum for package management, grep for searching text, ps and kill for processes.
  • chmod 755 means owner has read/write/execute, group and others have read/execute only.

macOS features

  • Finder is the file manager equivalent to Windows Explorer.
  • Spotlight is the built-in search tool.
  • Time Machine handles automatic backups to an external or network drive.
  • Keychain stores saved passwords and certificates.
  • Disk Utility formats drives and runs First Aid to repair disk errors.
  • Terminal gives access to the Unix-based shell beneath the GUI.

Common exam traps

  • Safe Mode loads Windows with minimal drivers — used for troubleshooting, not for normal use.
  • Task Manager (Windows) vs Activity Monitor (macOS) vs System Monitor (Linux) — same job, different names, do not mix them up.
  • Windows Update is mandatory for security patches on supported editions; disabling it long-term is a security risk.
  • Boot order and UEFI settings live in firmware setup, not the OS — press the vendor key (often Del, F2 or Esc) at startup.
  • Linux permissions use numeric shorthand (read=4, write=2, execute=1) — learn to add these up quickly.
  • Windows 11 needs TPM 2.0, UEFI Secure Boot, 4GB RAM and 64GB storage minimum.
  • Windows Home edition cannot join a domain or use BitLocker or gpedit.msc.
  • FAT32 has a hard 4GB maximum single file size.
  • NTFS supports file/folder permissions, EFS encryption and journaling; exFAT does not.
  • chmod 755 gives owner full rwx, group and others read+execute only.
  • sfc /scannow repairs corrupted Windows system files; chkdsk checks disk integrity.
  • macOS uses APFS as the default file system since macOS 10.13 High Sierra.
  • Time Machine is macOS's built-in automatic backup tool.
  • Task Manager (Windows), Activity Monitor (macOS) and System Monitor (Linux) all monitor running processes.
  • Safe Mode boots Windows with minimal drivers for troubleshooting purposes.
  • Linux chmod numeric values are read=4, write=2, execute=1, summed per user class.
  • apt and yum are Linux package managers, not available natively on Windows or macOS.
What are the four minimum hardware requirements for Windows 11?
4GB RAM, 64GB storage, TPM 2.0, and UEFI firmware with Secure Boot enabled.
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Which Windows editions support BitLocker and joining a domain?
Pro, Pro for Workstations and Enterprise — not Home.
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What is the maximum single file size on FAT32?
4GB.
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Which Windows command repairs corrupted system files?
sfc /scannow
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Which Windows command checks and repairs disk errors?
chkdsk
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What does chmod 755 grant on a Linux file?
Owner gets read, write and execute (7); group and others get read and execute only (5 each).
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What is the default file system on modern macOS?
APFS (Apple File System), default since macOS 10.13 High Sierra.
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What does Time Machine do on macOS?
It is the built-in tool for automatic, versioned backups to an external or network drive.
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What is the macOS equivalent of Windows Task Manager?
Activity Monitor.
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What does Safe Mode do in Windows?
Boots the OS with minimal drivers and services loaded, used to troubleshoot problems.
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Which Linux command changes file ownership?
chown
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Name two Linux package managers and the distro family each is associated with.
apt for Debian/Ubuntu-based systems, yum (or dnf) for Red Hat/Fedora/CentOS-based systems.
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What is the difference between an in-place upgrade and a clean install?
In-place upgrade keeps existing files, settings and apps; a clean install wipes the drive and starts fresh.
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Which Windows tool reapplies Group Policy settings immediately?
gpupdate /force
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What does exFAT lack compared to NTFS?
No file/folder permissions and no journaling, though it works well across Windows, macOS and large removable drives.
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Security fundamentals

Physical and device security

Physical controls stop the wrong person getting hands on a device or a room. Know these: badge readers, biometrics (fingerprint, retina, facial), mantraps (one person through at a time, stops tailgating), equipment locks (cable locks, laptop locks), server room access lists, and privacy/security screens (stop shoulder surfing). A guard or receptionist checking ID is a physical control too. Common mistake: candidates mix up 'tailgating' (an unauthorised person follows an authorised one through a door) with 'shoulder surfing' (watching someone type a password or PIN) - they are different attack types and both appear on the exam.

Logical security and authentication

AAA stands for Authentication, Authorisation, Accounting. Multifactor authentication (MFA) needs at least two different factor TYPES: something you know (password, PIN), something you have (smart card, authenticator app, hardware token), something you are (biometrics), somewhere you are (location), something you do (behaviour). Two passwords is NOT MFA - it is just two knowledge factors. Least privilege means giving users only the access they need to do their job, nothing more. Principle of least privilege plus role-based access control (RBAC) are the standard model for assigning permissions.

Malware and social engineering

Know the malware family: virus (needs a host file, needs user action to spread), worm (self-replicates across a network with no user action), trojan (disguised as legitimate software), ransomware (encrypts files and demands payment), spyware/keylogger (steals data or keystrokes), rootkit (hides deep in the OS, hard to detect). Social engineering attacks to know: phishing (email), vishing (voice/phone), smishing (SMS text), shoulder surfing, tailgating, dumpster diving, and whaling (phishing aimed at a senior executive). Common mistake: calling every email-based attack 'phishing' when the exam may specifically ask for spear phishing (targeted at one person/org) versus whaling (targeted at a C-level exec).

Wireless and network security basics

Wi-Fi encryption order from weakest to strongest: WEP (broken, never use), WPA, WPA2 (AES/CCMP), WPA3 (current standard, adds SAE for stronger handshake security). Always recommend WPA3, or WPA2 with AES if WPA3 isn't supported. A firewall filters traffic by port/protocol/IP; a VPN encrypts traffic over an untrusted network. Know that changing the default SSID and default admin password on a router are basic hardening steps, and that disabling SSID broadcast is weak security theatre, not a real control.

Mobile and data security

Know full device encryption, remote wipe, and screen locks (PIN/pattern/biometric) as core mobile protections. Data destruction methods: standard formatting is NOT secure erasure - use low-level format/overwrite, degaussing (magnetic media only, useless on SSDs), or physical destruction (shredding/drilling) for guaranteed disposal, especially for regulated data.

  • MFA requires at least two DIFFERENT factor types (know, have, are, somewhere, do) - two passwords is not MFA
  • AAA = Authentication, Authorisation, Accounting
  • WEP is broken and should never be used; WPA3 with SAE is the current recommended Wi-Fi standard
  • A worm self-replicates across a network with no user action; a virus needs a host file and user action
  • Tailgating is following someone through a secure door without authorisation; shoulder surfing is watching someone enter credentials
  • Whaling is phishing specifically targeted at a senior executive; spear phishing targets one specific person or organisation
  • A mantrap allows only one authenticated person through at a time and directly prevents tailgating
  • Ransomware encrypts a victim's files and demands payment for the decryption key
  • Standard formatting does not securely erase data - use overwrite, degaussing, or physical destruction instead
  • Degaussing works on magnetic media only and does nothing to an SSD
  • Least privilege means granting users only the access rights needed for their specific job role
  • A firewall filters traffic by port, protocol or IP address; a VPN encrypts the traffic itself over an untrusted network
What three factor types must MFA combine at minimum?
At least two DIFFERENT types from: something you know, something you have, something you are, somewhere you are, something you do
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What does AAA stand for in security?
Authentication, Authorisation, Accounting
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Which Wi-Fi encryption standard should never be used because it is broken?
WEP
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What is the current recommended Wi-Fi security standard and its key feature?
WPA3, which adds SAE (Simultaneous Authentication of Equals) for a stronger handshake
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Difference between a virus and a worm?
A virus needs a host file and user action to spread; a worm self-replicates across a network with no user action needed
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What is tailgating?
An unauthorised person follows an authorised person through a secure door without their own credentials
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What is shoulder surfing?
Watching someone enter a password, PIN or other sensitive data over their shoulder
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What is whaling?
A phishing attack specifically targeted at a senior executive or high-value individual
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What physical control stops more than one person entering through a secure door at a time?
A mantrap
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What does ransomware do?
Encrypts the victim's files and demands payment for the decryption key
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Why is standard formatting not enough to securely erase a drive?
It only removes the file table/pointers, not the underlying data - use overwrite, degaussing, or physical destruction instead
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Does degaussing work on an SSD?
No - degaussing only erases magnetic media like HDDs, it has no effect on solid-state drives
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What is the principle of least privilege?
Users are granted only the access rights necessary to perform their specific job, nothing more
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What is the key difference between a firewall and a VPN?
A firewall filters traffic by port, protocol or IP; a VPN encrypts the traffic itself as it crosses an untrusted network
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What is smishing?
A phishing-style social engineering attack delivered via SMS text message
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Troubleshooting hardware & software

The troubleshooting methodology (know this cold)

CompTIA tests a fixed six-step process. Learn the order, not just the steps.

1. Identify the problem - gather info, question the user, identify symptoms, check for changes, duplicate the problem if possible, approach multiple problems individually.

2. Establish a theory of probable cause - start with the obvious (Occam's razor), question the obvious.

3. Test the theory to determine cause - once confirmed, decide next steps. If not confirmed, re-theorise or escalate.

4. Establish a plan of action and implement the solution - research the knowledge base if needed.

5. Verify full system functionality and implement preventive measures if needed.

6. Document findings, actions, and outcomes.

Common mistakes candidates make

  • Skipping straight to 'implement a solution' without a confirmed theory - the exam punishes this.
  • Forgetting step 5's preventive measures half - verifying it works is not enough, you must also stop it recurring.
  • Mixing up 'establish theory' with 'test theory' - these are separate steps.
  • Not documenting - step 6 is always last and always required, even for a five-minute fix.

Hardware troubleshooting themes

  • POST beep codes and error codes point to specific failed components (RAM, video, motherboard) - manufacturer-specific, always check the board/BIOS vendor's chart.
  • Overheating symptoms: intermittent shutdowns, thermal throttling, fan noise - check airflow, reapply thermal paste, clear dust.
  • Power issues: no POST plus no lights usually means PSU, cabling, or a dead motherboard - swap known-good parts to isolate.
  • Storage: clicking drive = mechanical HDD failure sign; S.M.A.R.T. warnings should never be ignored.

Software troubleshooting themes

  • Boot problems: use Windows Recovery Environment (WinRE), Startup Repair, bootrec commands (/fixmbr, /fixboot, /rebuildbcd).
  • Application crashes: check Event Viewer logs first, then reinstall or update drivers/software.
  • Malware symptoms vs normal faults: unexpected pop-ups, renamed files, high CPU with no cause - follow the separate seven-step malware removal process, not the general six-step one.
  • Blue screens (BSOD): note the stop code, check Reliability Monitor and Event Viewer for the failing driver.

Exam tip

Questions often give you a scenario and ask 'what is the NEXT step' - map the scenario to the six steps in order and pick the very next one, not the best overall action.

  • The CompTIA troubleshooting methodology has exactly 6 steps, always in the same order.
  • Step 1 is identify the problem: gather info, question users, identify symptoms, check for recent changes.
  • Step 2 is establish a theory of probable cause - start with the obvious, question the obvious.
  • Step 3 is test the theory to determine cause before doing anything else.
  • Step 4 is establish a plan of action and implement the solution, researching if needed.
  • Step 5 is verify full system functionality AND implement preventive measures - both parts matter.
  • Step 6 is document findings, actions, and outcomes - always the final step, never skipped.
  • Malware removal follows its own separate 7-step process, distinct from the general 6-step method.
  • No POST and no lights usually points to the PSU, cabling, or motherboard - isolate with known-good swaps.
  • bootrec /fixmbr, /fixboot, and /rebuildbcd are the standard Windows boot-repair commands.
  • S.M.A.R.T. warnings on a drive should always be treated as an imminent failure risk.
  • Event Viewer and Reliability Monitor are the first places to check for BSOD stop codes and app crash causes.
How many steps are in the CompTIA troubleshooting methodology?
Six, always performed in the same fixed order.
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What is step 1 of the troubleshooting methodology?
Identify the problem - gather info, question the user, identify symptoms, check for recent changes.
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What is step 2 of the troubleshooting methodology?
Establish a theory of probable cause, starting with the most obvious explanation.
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What is step 3 of the troubleshooting methodology?
Test the theory to determine cause, before implementing any fix.
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What is step 4 of the troubleshooting methodology?
Establish a plan of action and implement the solution, researching the knowledge base if needed.
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What two things must happen in step 5?
Verify full system functionality AND implement preventive measures.
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What is the final step of the troubleshooting methodology, and can it be skipped?
Step 6, document findings actions and outcomes - never skipped, even for quick fixes.
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Does malware removal follow the standard 6-step process?
No, it has its own separate 7-step process.
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A PC has no POST and no lights - what should you suspect first?
PSU, cabling, or a dead motherboard - isolate using known-good component swaps.
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What symptom strongly suggests mechanical hard drive failure?
A clicking noise from the drive.
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Which Windows commands repair the boot sector, boot files, and BCD?
bootrec /fixmbr, bootrec /fixboot, and bootrec /rebuildbcd.
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Where should you check first for the cause of a BSOD?
The stop code, plus Reliability Monitor and Event Viewer for the failing driver.
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Where should you check first when an application keeps crashing?
Event Viewer logs, then consider reinstalling or updating drivers and software.
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What principle underlies step 2, establishing a theory?
Occam's razor - start with the simplest, most obvious explanation first.
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An exam question asks for the NEXT step in a scenario - how should you answer?
Map the scenario onto the six-step order and pick the very next step, not the overall best fix.
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Operational procedures & safety

Safety basics

Electrostatic discharge (ESD) is the top hazard for components. Always wear an anti-static wrist strap connected to a grounded point, and use anti-static bags for storage and transport. If no strap is available, self-ground by touching the case chassis before touching parts.

Electrical safety matters just as much. Always unplug a device before opening the case. When working inside a power supply or CRT monitor, never open the casing yourself - these hold a lethal charge even when unplugged, so leave them to trained techs. Use an ESD mat on the workbench to protect components further.

Fire safety

Know your fire extinguisher classes. Class A is for ordinary combustibles like wood and paper. Class B is for flammable liquids. Class C is for electrical fires - never use water or a Class A extinguisher on live electrical equipment. Class D is for combustible metals. A Class ABC extinguisher covers most office and workshop situations.

Lifting and ergonomics

When lifting heavy equipment such as a server or printer, lift with your legs not your back, keep the load close to your body, and get help or a trolley for anything over roughly 40 lbs (about 18 kg). Poor posture at a workstation causes long-term injury, so keep monitors at eye level and use proper chair support.

Environmental and disposal rules

Environmental controls matter for equipment longevity: keep humidity moderate to avoid ESD (too dry) or corrosion (too damp), and keep temperature controlled with good airflow. Material Safety Data Sheets (MSDS), now called SDS (Safety Data Sheets), tell you how to handle hazardous materials safely and what to do in an incident - know where to find them.

Dispose of batteries, toner cartridges, and CRT monitors according to local regulations - never in general rubbish, since they contain hazardous materials. Follow your organisation's environmental policy for e-waste recycling.

Professionalism and communication

A+ techs must show good professional behaviour: maintain a positive attitude, avoid jargon with customers, actively listen, avoid distractions like personal calls while working, and set clear, realistic expectations with the customer. Deal with difficult customers or situations calmly and without arguing.

Common mistakes to avoid

  • Forgetting to unplug equipment before internal work.
  • Skipping the anti-static strap and frying a component with ESD.
  • Using the wrong extinguisher class on an electrical fire.
  • Ignoring MSDS/SDS guidance when handling chemicals or hazardous waste.
  • Lifting heavy kit alone instead of asking for help.
  • Always unplug a device before opening the case to work inside it.
  • Wear an anti-static wrist strap connected to ground to prevent ESD damage to components.
  • Never open a power supply or CRT monitor casing yourself - they retain lethal charge even unplugged.
  • Class C fire extinguishers are for electrical fires - never use water on live electrical equipment.
  • Class A extinguishers suit ordinary combustibles like paper and wood.
  • Class D extinguishers are for combustible metal fires.
  • Get help or use a trolley to lift equipment over roughly 40 lbs (18 kg).
  • Lift with your legs, not your back, and keep loads close to the body.
  • MSDS/SDS (Material Safety Data Sheets / Safety Data Sheets) detail safe handling of hazardous materials.
  • Batteries, toner cartridges and CRT monitors must be disposed of per local environmental regulations, not general rubbish.
  • Keep workshop humidity moderate - too dry raises ESD risk, too damp risks corrosion.
  • Professional conduct requires avoiding jargon, active listening, and avoiding personal distractions with customers.
What is the number one hazard to electronic components during hands-on work?
Electrostatic discharge (ESD)
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What should you always do before opening a computer case?
Unplug the device from power first
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Should you ever open a power supply or CRT monitor casing yourself?
No - they can hold a lethal charge even when unplugged; leave to trained technicians
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Which fire extinguisher class is for electrical fires?
Class C
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Which fire extinguisher class is for ordinary combustibles like paper and wood?
Class A
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Which fire extinguisher class covers flammable liquids?
Class B
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Which fire extinguisher class covers combustible metals?
Class D
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What is the safe approximate weight limit before you should get help or a trolley to lift equipment?
Around 40 lbs (18 kg)
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What is the correct lifting technique for heavy equipment?
Lift with your legs, not your back, keeping the load close to your body
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What document tells you how to safely handle a hazardous chemical or material?
The MSDS/SDS (Material Safety Data Sheet / Safety Data Sheet)
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How should batteries and CRT monitors be disposed of?
According to local environmental regulations - never in general rubbish
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What protects components on the workbench from ESD besides a wrist strap?
An anti-static mat and anti-static bags for storage/transport
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Name two environmental factors to control in a workshop or server room.
Humidity (moderate, to avoid ESD or corrosion) and temperature/airflow
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What is a key professional behaviour when dealing with a difficult customer?
Stay calm, avoid arguing, actively listen, and avoid jargon
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What should you do if no anti-static wrist strap is available?
Self-ground by touching the case chassis before touching internal parts
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