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UE5 fails to initialize. Assertion failed: IsValid() [File:D:/build/++UE5/Sync/Engine/Source/Runtime/Core/Private/Windows/WindowsPlatformFile.cpp] [Line: 602]

Restart does nothing, reinstall does nothing. Running on:
Win 10, 32gb ram, i7 9th gen, rtx 2070 (latest drivers). UE4 initializes but can’t load any projects.

Here’s the full log:
Assertion failed: IsValid() [File:D:/build/++UE5/Sync/Engine/Source/Runtime/Core/Private/Windows/WindowsPlatformFile.cpp] [Line: 602]

UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_Engine
UnrealEditor_Engine
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_Engine
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor_CoreUObject
UnrealEditor
UnrealEditor
UnrealEditor
UnrealEditor
UnrealEditor
kernel32
ntdll

I had the same issue.
I uninstalled and re-installed UE5 on my C drive instead of D and those errors went away.