# ROOT CAUSE ANALYSIS: GUI Launch Failure

## Error Details
- **Exit Code:** -1073740771 (0xC0000409)
- **Error Type:** STATUS_STACK_BUFFER_OVERRUN
- **Severity:** CRITICAL - Memory corruption/stack overflow

## Root Cause

### Primary Issue
The testing protocol **FAILED** to test actual GUI window creation. The test only verified:
1. ✅ Module syntax (PSParser tokenization)
2. ✅ Module loading (dot-sourcing)
3. ✅ Function existence (Get-Command)

**MISSING:** Actual XAML parsing and window creation test

### Why This Slipped Through

1. **Incomplete Test Coverage**
   - Test only checked if `Start-GUI` function exists
   - Never actually CALLED `Start-GUI` to parse XAML
   - Never attempted to create the WPF window
   - XAML parsing happens INSIDE `Start-GUI`, which was never executed

2. **Stack Buffer Overrun Causes**
   - XAML string is very large (~6000+ lines)
   - XAML parsing creates deep object hierarchies
   - Memory allocation during XAML parsing can exceed stack limits
   - Possible circular references or malformed XAML structure

3. **Missing Safety Checks**
   - No memory usage monitoring
   - No stack depth validation
   - No XAML size limits
   - No actual window creation test

## Fixes Required

1. **Add Actual GUI Window Creation Test**
   - Parse XAML and create window (then immediately close)
   - Test in isolated AppDomain if possible
   - Monitor memory usage during test

2. **Improve XAML Parsing Error Handling**
   - Wrap XAML parsing in try-catch with memory monitoring
   - Add stack overflow detection
   - Provide fallback if XAML is too large

3. **Enhanced Testing Protocol**
   - MUST test actual window creation, not just function existence
   - MUST test XAML parsing in isolation
   - MUST monitor memory/stack usage
   - MUST test in same environment as production

## Testing Protocol Improvements

### New Requirements
1. **Syntax Test** ✅ (Already exists)
2. **Module Load Test** ✅ (Already exists)
3. **Function Existence Test** ✅ (Already exists)
4. **XAML Parse Test** ❌ (MISSING - CRITICAL)
5. **Window Creation Test** ❌ (MISSING - CRITICAL)
6. **Memory Safety Test** ❌ (MISSING - CRITICAL)
