220-1202 cheat sheet: CompTIA A+ Core 2

Operating systems

Windows editions and licensing (Home, Pro, Pro for Workstations, Enterprise) differ mainly in domain join, BitLocker, and Remote Desktop host support.
Command-line basics: ipconfig, ping, tracert, sfc /scannow, chkdsk, and the difference between running Command Prompt as a standard user vs. as Administrator.
File systems: NTFS (permissions, encryption, journaling — the Windows standard) vs. exFAT (cross-platform, no permissions, used for large removable drives) vs. FAT32 (legacy, 4 GB file-size limit).
macOS and Linux basics: Finder/Terminal vs. Explorer/Command Prompt equivalents, package managers (apt, yum) on Linux, and common file-permission notation (rwx) on both.

Malware types: virus, worm, trojan, ransomware, rootkit, keylogger, spyware — know the distinguishing behaviour of each, not just the name.
Authentication and access: least privilege, multifactor authentication factors (know/have/are), and the difference between authentication and authorization.
Physical and workstation security: cable locks, badge/biometric readers, screen locks with a timeout, and secure disposal (drive wiping, shredding, degaussing) for retired hardware.
Windows security features: Windows Defender/Firewall, BitLocker (full-disk encryption), User Account Control (UAC) prompts, and NTFS vs. share permissions (the more restrictive one wins when they combine).

Malware removal order: identify and quarantine → disable System Restore → remediate (update definitions, scan, remove) → schedule scans and updates → re-enable System Restore and create a restore point → educate the end user.
Common OS symptoms and likely fixes: slow boot (too many startup items), application won't launch (corrupt install, missing dependency), blue screen (driver or hardware fault — check Event Viewer).
Mobile OS troubleshooting: unresponsive app (force-stop and restart), no connectivity (toggle airplane mode, check for a carrier outage), unauthorized account access (revoke device access, change credentials).
PC security symptom triage: pop-ups and redirected browsing point to adware/a hijacked browser extension; unexpected outbound network activity points to something already installed and phoning home.

Change management: document the proposed change, get approval, have a rollback plan, and communicate the maintenance window before making it.
Safety: know ESD (electrostatic discharge) precautions — anti-static wrist straps, mats — and where to find a Safety Data Sheet (SDS) for a chemical or toner cartridge.
Documentation: incident reports, asset/inventory management, and knowledge-base articles all matter for the next technician, not just the current ticket.
Professionalism: active listening, avoiding jargon with end users, setting and meeting expectations, and maintaining confidentiality are explicitly tested, not just implied soft skills.

Reading a summary is the easy part. Take the free 10-question diagnostic to see which of these domains you actually have, then drill the rest.