# Lab TRB-4: PC Security Symptom Triage

Domain:
- 3.0 Software Troubleshooting

Works on:
- Windows
- Linux comparison optional

## Goal

Practice security symptom triage without changing browser profiles or deleting files.

## Part 1: Browser Checks

Record:
- Browser extension count:
- Default search engine:
- Proxy setting location found:
- Certificate warning seen on normal sites, yes or no:
- Pop-up and notification permissions location found:

## Part 2: Windows Checks

Windows:

```powershell
Get-ComputerInfo | Select-Object OsName,OsVersion
Get-Date
netsh winhttp show proxy
```

Record:
- OS version:
- System date/time:
- Proxy status:

## Part 3: Scenario Triage

For each symptom, list likely cause and first action:

1. Files are renamed and cannot be opened.
2. Browser searches redirect to an unfamiliar site.
3. Fake antivirus warnings demand payment.
4. Windows Update fails on a previously infected PC.
5. A banking site certificate warning appears.

## What You Should Learn

- Security troubleshooting starts with symptoms and risk.
- Some symptoms require isolation before normal repair.
- Browser settings, proxy settings, date/time, and extensions can explain many security symptoms.