LoginId:4f2bf060459ff7bdf6a449a3a2819d93
EpicAccountId:361f8acd259042539e04cf2ecb447376
Assertion failed: NumBytes == Strings.Num() [File:D:/build/++UE5/Sync/Engine/Source/Runtime/Core/Private/UObject/UnrealNames.cpp] [Line: 3357]
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_AssetRegistry
UnrealEditor_AssetRegistry
UnrealEditor_Core
UnrealEditor_Core
kernel32
ntdll
I already reinstalled UE5, I updated my GPU, I verifyed the engine, I also tried cloning the project. Nothing is working right now. All my hard work is gone now, not even the autosaves backups are working properly.
I’m having the exact same issue. It worked 20 minutes before… now all of a sudden my project won’t start. Sooo much work seems to be lost 
I just copied my project folder to do some trial and error testing.
After seeing the below copied message in the latest log (along with other error lines), I just tried my luck and deleted the CachedAssetRegistry.bin file in the Intermediate folder of the project.
So with this file deleted, I can finally start the project again.
[2021.06.18-14.11.13:057][ 0]LogThreadingWindows: Error: Runnable thread FAssetDataGatherer crashed.
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Unfortunately, when wanting to open the map I worked on the last time before this issue happened, I get this message “Failed to open map file. This is most likely because the map was saved with a newer version of the engine.”
Luckily I still have a slightly older copy of this map which I can open.
But maybe someone knows if there’s a way to restore the proper map file even after deleting the CachedAssetRegistry.bin?
I’m having crashes when opening certain blueprints.
