winui x coreclr bug - c0000005 code

Question

I have 0 idea about the relationship between WinUI 3 and CoreCLR, to be clear.

3 projects of WinUI 3 are failing with the same error code.

No matter what I try — DISM, SFC, reinstalling all .NET packs (even using more "stable" versions), I even downloaded the full VS Community 2026 kit with the WinUI kit included — nothing fixes it.

Problem signature:
P1: Microsoft.WinUI3ControlsGallery_2.9.3.0_x64__8wekyb3d8bbwe
P2: praid:App
P3: 2.9.3.0
P4: 69f20000
P5: coreclr.dll
P6: 9.0.1626.22923
P7: 69f29075
P8: c0000005
P9: 00000000002e4ff2
P10: 

And honestly, I'm not sure if this collides with the Search app that's already broken:

Problem signature:
P1: Microsoft.Windows.Search_1.14.18.19041_neutral_neutral_cw5n1h2txyewy
P2: praid:CortanaUI
P3: 10.0.19041.6282
P4: 87634c04
P5: ConstraintIndex.Search.dll
P6: 10.0.19041.5794
P7: 9ba14ef4
P8: c0000005
P9: 00000000000bb2b3
P10: 

Here's another log, this time totally fresh and plain — no edits on it at all:

Problem signature:
P1: E51BB32E-3AC8-4193-B91C-C7A02E25C481_1.0.0.0_x64__1z32rh13vfry6
P2: praid:App
P3: 1.0.0.0
P4: 6a0e0000
P5: coreclr.dll
P6: 10.0.926.27113
P7: 6a0e0671
P8: c0000005
P9: 0000000000356fef
P10: 

The app was run via dotnet run.

Answer 1

Hello @Soterana00 Yt ,

Thanks for your question.

The c0000005 error means Access Violation. It occurs when an application tries to access memory it is not permitted to use, causing Windows to terminate the process.

For WinUI 3 apps, this happens when CoreCLR interacts with the graphics subsystem and encounters issues caused by outdated or corrupted graphics drivers, or by third-party software injecting into the app process.

You can refer to these following steps:

1. Perform a Clean Boot

• Disable third-party startup services and applications using Microsoft's Clean Boot guide.
• Launch the WinUI 3 Controls Gallery app and check if the issue persists.

2. Clean-install graphics drivers.

• Download the latest driver from NVIDIA, AMD, or Intel.
• Use the vendor's Clean Install option to remove previous driver configurations.

3. Review Event Viewer logs

• Press Win + R, type eventvwr, and press Enter.
• Navigate to Windows Logs > Application.
• Look for Event ID 1000 (Application Error) at the time of the crash and note the failing module details.

I hope this addresses your question. If this response was helpful, please consider following the guidance to provide feedback. Thank you.