Engine C++ files keep getting deleted / missing

[Xomer]

After Upgrading from UE 5.2.1 to 5.5.0 or 5.5.1 random Engine files keep getting deleted when starting the Unreal Development Editor in DebugMode over VS2022 after Reboots.

The missing files are always different, but are most of the time located in the Runtime\Core or Runtime\CoreUObject folder.
Today after 2 weeks working without issues the file “UnrealEngine-5.5.0-release\Engine\Source\Runtime\Core\Public\Templates\UnrealTypeTraits.h” was suddenly missing.
The files can not be found and restored in the bin but are just suddenly disappearing.

I had to extract the original files again from the .zip and put it into the corresponding folder and wait 2-3 hours for the whole Engine to compile again…
Other files I wrote down who suddenly disappeared in the past have been (sometimes also the .cpp files):
UnrealEngine-5.5.0-release\Engine\Source\Runtime\CoreUObject\Public\UObject\ClassTree.h
UnrealEngine-5.5.0-release\Engine\Source\Runtime\Core\Public\Internationalization\TextNamespaceUtil.h

I already disabled HotReload and LiveCoding.
I use the Unreal GitHub version building from the released source on a Windows 10 PC.

Now my suspicion is the newly added Fab-Plugin, which I will turn off after the compile is finished.
I also have some port blocking .NetHost issues when stopping and restarting the Editor.

I didn’t see any posts regarding these issues, please fix the Engine, 5.2.1 worked much better for me…

[Xomer]

Haven’t had this issue so far for the last month.
The two things I changed simultanously which one of them fixing it (my guess is second):

1. Upgraded to UE 5.5.3 github release build
2. Changed to process of starting up the Development-Editor

• Previously: Starting VS2022 in Administrator and opening the project and start debugging from there.
• Now: Double-Clicking the project.sln which opens VS2022 in normal mode and start debugging from there.

My guess is that the admin VS2022 unloading process messes somehow up the included UE5 project files.

Still have livecoding, hotreload and fab off just in case.
Turning fab only on when I have an asset to import.

Blocking .NET Ports / Processes still a thing though if you quickly stop and start debugging again after a code change and recompile.