Yep! That’s the callstack! Same error listed as the inciting error, but the full trace this time. The BufferReader header’s failing, which can mean a decent number of things. The basics of it is that whatever it’s checking that assertion against is wrong.
I haven’t seen this one before but since it’s a core function it’s a tough one to debug.
Looking into the other vein, these two lines also stand out:
[2023.09.30-17.01.33:625][463]LogLinker: Warning: [AssetLog] U:\Unreal\Projects\Space Scene\Space\Content\Space.umap: Failed to load '/Game/Asteroids/Asteroids': Can't find file.
and
[2023.09.30-17.01.33:625][463]LogLinker: Warning: [AssetLog] U:\Unreal\Projects\Space Scene\Space\Content\Space.umap: VerifyImport: Failed to load package for import object 'Package /Game/Asteroids/Asteroids'
It looks like it’s failing to open this map because it can’t find the file. Does the file still exist?
If possible and you have another map, can you change the DefaultEngine.ini to pick a different starting map? For example:
[/Script/EngineSettings.GameMapsSettings] EditorStartupMap=/Game/ThirdPerson/Maps/ThirdPersonMap.ThirdPersonMap GameDefaultMap=/Game/ThirdPerson/Maps/ThirdPersonMap.ThirdPersonMap