CompTIA A+ Core 2 | Domain 8: Software Troubleshooting (23%) | Reading (7 & 8)

 

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8.1 Troubleshooting Methodology (Review)

Always follow the standard 6-step process:

1. Identify the problem
   2. Establish a theory of probable cause
   3. Test the theory
   4. Establish a plan of action and implement solution
   5. Verify functionality
   6. Document findings

Do NOT skip steps on the exam
Many questions test the order

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8.2 Common Windows OS Issues

Slow Performance

Causes:

• Too many startup programs
• Insufficient RAM
• Malware infection
• Fragmented HDD

 

Solutions:

• Disable startup apps (Task Manager → Startup tab)
• Add RAM
• Scan for malware
• Use Disk Cleanup / Defrag (HDD only)

 

System Freezing / Crashing

 

 Causes:

• Driver conflicts
• Overheating
• Corrupt system files

 

Solutions:

• Update drivers
• Run system diagnostics
• Use system repair tools

 

Blue Screen (BSOD)

 

Causes:

• Hardware failure
• Bad drivers
• Corrupt OS

 

Solutions:

• Check error codes
• Update/rollback drivers
• Run memory tests

 

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8.3 Boot Issues

 

System Won’t Boot

 

Causes:

• Missing OS files
• Corrupt bootloader

 

Tools:

 

Safe Mode

• Loads minimal drivers
• Used for troubleshooting

 

Recovery Environment (WinRE)

• Startup Repair
• System Restore
• Command Prompt

 

Commands:

bootrec /fixmbr
bootrec /fixboot
bootrec /rebuildbcd

 

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8.4 Application Issues

 

Application Won’t Open

 

Causes:

• Corrupt install
• Compatibility issues

 

Fix:

• Reinstall application
• Run as administrator
• Use compatibility mode

 

Application Slow

 

Causes:

• Low system resources
• Background processes

 

Fix:

• Close unused apps
• Upgrade hardware

 

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8.5 Driver Issues

 

What is a Driver?

Software that allows OS to communicate with hardware

 

Driver Problems

 

Symptoms:

• Device not working
• Errors in Device Manager

 

Fix:

• Update driver
• Roll back driver
• Reinstall driver

 

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8.6 Malware Issues

 

Symptoms:

• Pop-ups
• Slow performance
• Unknown programs

 

Removal Process:

1. Identify malware
   2. Quarantine system
   3. Remove malware
   4. Update system
   5. Educate user

 

 Tools:

• Antivirus
• Anti-malware

 

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 8.7 Network-Related Software Issues

 

No Internet (Software Side)

 

Causes:

• Incorrect IP config
• DNS issues
• Firewall blocking

 

Fix:

• Use ipconfig
• Flush DNS:

ipconfig /flushdns

• Reset network adapter

 

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8.8 Windows Tools for Troubleshooting (EXAM CRITICAL)

 

Tools You MUST Know

Tool	Purpose
Task Manager	Manage processes
Device Manager	Hardware/drivers
Event Viewer	Logs/errors
System Configuration (msconfig)	Startup control
Services	Background services

 

 

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 8.9 Command-Line Troubleshooting

 

Commands:

sfc /scannow   → Repair system files
chkdsk         → Check disk
tasklist       → List processes
taskkill       → Kill process
ipconfig       → Network info
ping           → Connectivity

 

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8.10 Mobile OS Troubleshooting

 

Common Issues

 

Battery Drain

• Background apps
• High brightness

 

No Connectivity

• Airplane mode
• Network misconfiguration

 

 App Crashes

• Outdated apps
• Corrupt cache

 

 Fix:

• Restart device
• Update apps/OS
• Clear cache

 

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8.11 macOS & Linux Troubleshooting

 

macOS Issues:

• App crashes → reinstall
• Slow system → Activity Monitor

 

Linux Issues:

• Permission errors → chmod
• Command errors → check syntax

 

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 8.12 System Recovery Options

 

Windows Recovery Tools:

• System Restore
• Reset this PC
• Recovery Drive

 

 Use Cases:

• Corrupt OS
• Malware infection
• Failed updates

 

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8.13 Troubleshooting Scenarios (PBQ STYLE)

 

Scenario 1:

PC boots to blue screen
Likely: driver or hardware issue

 

Scenario 2:

App crashes after update
Likely: compatibility issue

 

Scenario 3:

Internet works on other devices but not one PC
Likely: IP/DNS issue

 

Scenario 4:

System very slow + pop-ups

Likely: malware

 

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8.14 Preventive Maintenance

• Keep OS updated
• Update drivers
• Run antivirus scans
• Remove unused programs
• Monitor system performance

 

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 8.15 Exam Tips (CRITICAL)

 

• Know Safe Mode & recovery tools
• Memorize commands (sfc, chkdsk, bootrec)
• Understand driver troubleshooting
• Recognize malware symptoms
• Focus on scenario-based questions

 

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Quick Knowledge Check

 

1. Command to repair system files?
   A. chkdsk
   B. sfc /scannow
   C. ping
   D. netstat

2. What causes BSOD?
   A. Printer
   B. Driver/hardware issue
   C. Mouse
   D. Keyboard

3. Tool to view logs?
   A. Task Manager
   B. Event Viewer
   C. BIOS
   D. CMD

4. What fixes bootloader issues?
   A. ipconfig
   B. bootrec
   C. ping
   D. format

5. App crashes usually caused by?
   A. Hardware only
   B. Compatibility issues
   C. RAM only
   D. Power supply

 

 

 Answers: 1-B, 2-B, 3-B, 4-B, 5-B

 

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Videos

Section 3: Software Troubleshooting

3.1 – Troubleshooting Windows

3.2 – Troubleshooting Mobile Devices

3.3 – Troubleshooting Mobile Device Security

3.4 – Troubleshooting Security