Can't switch or migrate to new engine! Unknown function crash

Development Programming & Scripting
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1

Hi all.

I am trying to update a project from 4.27 to 5.4

I have tried various methods to switching engine versions, but every time leads to some form of crash.

My last effort has left me dumbfounded:

  1. Create new clean project in 5.4
  2. Migrate across content folder from the 4.27 project
  3. Open 5.4 project (success) to default third person template map
  4. Try to open any other level or migrated blueprint results in a crash

Here is the attached crash log.

EcoRonin5.log (302.5 KB)

And the error shown by the engine at the time of crash:

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0xffffffffffffffff

UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Engine
UnrealEditor_CoreUObject

etc. etc…

I am out of ideas and at the end of my rope, any help or suggestions are much appreciated!

Thanks!

p.s. here is some more info about things I have tried here:Can't update project to UE5