1. Introduction to Troubleshooting

1.1 What is Troubleshooting?

Troubleshooting is a systematic process of identifying, diagnosing, and resolving computer hardware or software problems.

Key Takeaway: It is not guessing. It is a logical problem-solving approach.

2. Standard Troubleshooting Methodology

The Industry Approach - Memorize this structured method.

01

Identify the Problem

  • Ask the user what happened
  • Observe symptoms
  • Check error messages
  • Note recent changes (updates, installations, power cuts)
02

Establish a Theory

  • What could cause this issue?
  • Hardware or software?
  • Recent driver update?
  • Overheating? Virus?
03

Test the Theory

  • Run diagnostics
  • Boot into Safe Mode
  • Check Device Manager
  • Try known working components
04

Establish Plan & Fix

  • Repair, replace, reinstall, update, rollback
05

Verify Functionality

  • Restart
  • Test application & internet
  • Stress test if required
06

Document Solution

  • Write problem, cause, fix
  • Provide preventive advice

3. Understanding Computer Components

CPU (Processor)

Brain of the computer

Executes instructions.

⚠ Overheating causes shutdown

RAM

Temporary memory

⚠ Faulty RAM causes crashes & blue screens

Storage (HDD / SSD)

Stores OS and files

⚠ Bad sectors cause slow boot

Power Supply (SMPS)

Provides power

⚠ Fault causes no boot

Motherboard

Connects all components

⚠ Failure causes no display or random shutdown

  • Operating System (Windows / Linux)
  • Drivers (Crucial for hardware communication)
  • Applications (User software)
  • System Services (Background processes)
  • Antivirus (Security software)

4. Drivers – Complete Teaching Section

A driver is a software program that allows the OS to communicate with hardware devices. Without a driver, hardware does not function properly.

  • Wi-Fi driver → enables internet
  • Display driver → enables graphics
  • Audio driver → enables sound
  • OS update incompatible with driver
  • Driver corrupted or missing
  • Wrong driver installed
  • Hardware replaced without installing driver
  • Wi-Fi not showing
  • No sound or low display resolution
  • USB not detected
  • Device showing yellow warning in Device Manager
  1. Open Device Manager (Check for yellow warning).
  2. Identify Problem Device (Network, Display, Audio).
  3. Solutions: Update, Rollback, Reinstall, or Download from manufacturer website.

Problem: Wi-Fi not working after Windows installation.

Diagnosis: Network driver missing.

Fix: Download correct driver from laptop manufacturer site -> Install -> Restart -> Verify.

  • Always install drivers from official website.
  • Avoid random driver update software.
  • Create restore point before updating drivers.

5. Boot Problems

5.1 Types of Boot Problems

  • No power
  • No display
  • Stuck on logo
  • Automatic restart
  • "No bootable device found"

5.2 No Power Troubleshooting

  • Check Power cable, Adapter, Power button
  • Check SMPS, RAM seating

5.3 No Display Troubleshooting

  • Check monitor
  • Remove and reseat RAM
  • Reset BIOS (remove CMOS battery)
  • Test external display (for laptop)

5.4 No Bootable Device Error

Causes: HDD failure, OS corruption, Wrong BIOS boot order.

Fix: Check BIOS boot order, Run disk diagnostics, Reinstall OS.

6. Slow Performance Issues

6.1 Common Causes

  • Low RAM
  • Full Storage
  • Virus
  • Startup Apps
  • Old HDD

6.2 Troubleshooting

  • Check Task Manager (CPU, RAM, Disk)
  • Disable unnecessary startup apps
  • Scan for malware
  • Upgrade to SSD & Increase RAM

Classroom Scenario

Student complains laptop is slow. Observation: 100% Disk usage. Cause: Old HDD + Updates. Solution: Upgrade to SSD + Clean install.

Quick Reference Guides

7. Overheating

Causes: Dust, dried thermal paste, blocked vents.

Fix: Clean fan, replace thermal paste, cooling pad.

8. Blue Screen (BSOD)

Windows crash screen.

Fix: Note error code, Safe Mode, Memory test, Update drivers, SFC scan.

9. Network Issues

Wi-Fi not detected, Slow internet.

Fix: Check router, Restart modem, Drivers, Flush DNS, Reset network.

10. Virus & Malware

Slow system, Popups.

Fix: Antivirus scan, Remove suspicious software, Reset browser.

11. BIOS Issues

Wrong boot order, Date reset.

Fix: Reset BIOS, Update BIOS, Replace CMOS battery.

12. Hardware Failure

Clicking sound, Beeps, Burning smell.

Tools: Memory Diagnostic, SMART check, BIOS test.

13. Advanced Techniques

  • Safe Mode boot
  • System Restore
  • Event Viewer logs
  • Command Prompt / Chkdsk
  • Clean OS installation

14. Preventive Maintenance

  • Regular dust cleaning
  • Genuine Antivirus
  • Keep drivers updated
  • Backup important data
  • Monitor temperature