CompTIA A+ (220-1202): Software Troubleshooting
Table of Contents
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Software Troubleshooting is 23% of the CompTIA A+ 220-1202 Core 2 exam. This module covers Windows OS issues, mobile OS and application problems, security symptoms, and malware removal. Pair this domain with the Core 1 troubleshooting methodology because the same process applies to software.
Software problems frustrate users and fill the ticket queue. You read the symptoms, match them to a cause, and apply the fix that solves the problem without losing data. This module covers the software faults you will see most.
Windows OS Troubleshooting
You diagnose the common Windows failures.
| Symptom | Likely cause | Fix |
|---|---|---|
| BSOD / stop error | Bad driver, RAM, or hardware | Check driver, run memory test |
| Boot failure | Corrupt boot files | Startup Repair, bootrec |
| Frequent shutdowns | Overheating or PSU | Check temps and power |
| Services not starting | Dependency or corruption | Check Services and Event Viewer |
| Slow performance | Startup bloat, low disk, malware | Trim startup, free space, scan |
| Time drift | Dead CMOS battery or NTP | Replace battery, sync time |
You repair core files from the command line:
sfc /scannow # Repair system files
DISM /Online /Cleanup-Image /RestoreHealth # Repair the component store
chkdsk C: /f /r # Fix filesystem and recover sectors
Mobile OS and Application Issues
You fix phones and tablets that misbehave.
- Apps failing to launch or crashing call for an update, cache clear, or reinstall.
- Battery drain points to a rogue app, poor signal, or background activity.
- Random reboots suggest an OS bug, a bad update, or failing hardware.
- Slow performance traces to low storage or too many background apps.
- Connectivity problems need a check of Wi-Fi, cellular, Bluetooth, and airplane mode.
Mobile Security Issues
You spot signs that a mobile device is compromised.
| Symptom | Concern |
|---|---|
| Jailbreak / root detected | Security controls bypassed |
| High network traffic | Data exfiltration or malware |
| Fake security warnings | Scareware or a malicious app |
| Unexpected app permissions | Spyware or overreaching app |
| Unusual battery drain | Hidden background activity |
Removing root or jailbreak and reinstalling from a clean image restores trust.
PC Security Symptoms
You recognize a compromised desktop.
- Desktop alerts and fake antivirus warnings are scareware.
- Altered or renamed files can signal ransomware.
- Browser redirection and frequent pop-ups point to adware or a hijacked browser.
- Certificate warnings can indicate a man-in-the-middle attack.
- New, unknown toolbars or extensions are often malicious.
A privacy-focused browser reduces this risk. See the best privacy browsers .
Malware Removal Techniques
You remove stubborn malware with the right tools.
- Safe Mode loads minimal drivers so malware cannot block your scan.
- Preinstallation environments (WinPE) scan offline before Windows loads.
- Reimaging wipes and restores a clean OS image when removal fails.
- System Restore rolls back to a clean point, though sophisticated malware can survive it.
Follow the full seven-step process detailed in the Security module . Verify file integrity after cleanup using how to get hashes of files in Windows .
Next Steps
Finish Core 2 with Operational Procedures . Review the Security module for malware types and the Operating Systems module for repair tools. Return to the CompTIA A+ Course and take the CompTIA A+ Practice Test .
