Critical error on start up

I’m using Perforce P4V on a modding project.
It’s been working great so far, however today the editor is refusing to open.
I’m not entirely tech-savvy when it comes to UE4 so I don’t know what to look for.

Everytime I open the project, it loads to about 70% (sometimes not even 5) and will throw up an error report.
I’ve tried deleting my saved and intermediate folders, and getting latest from Perforce.

Help would be appreciated

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