Have you opened up your projects.xml file (in Documents > SDL Studio 2019 > Projects by default). One possibility could be that your projects.xml file is corrupted (I had problems with mine when I ran out of space in my Documents folder). 

Have you opened up your projects.xml file (in Documents > SDL Studio 2019 > Projects by default). One possibility could be that your projects.xml file is corrupted (I had problems with mine when I ran out of space in my Documents folder). 

Thanks for your quick reply Michael. I can open the projects.xml fine. I noticed that the actual projects are no longer being recognised as Studio projects (blank logo) which wasn't the case this morning.

I'm also wondering why the additional information in the error message seems to be referring to a non-existent OneDrive file.

Thanks anyway for your suggestion.

Hello Christine Hokamp ,

Have you tried resetting Studio?

https://gateway.rws.com/csm?id=kb_article_view&sysparm_article=KB0033669

Also, you mention blank logos/icons.

Where are you seeing these? In your projects folder?

Are you able to post a screenshot of what you are seeing please.

Yes, the sdlproj icon is normally recognizable as an sdl file but not below. When I tried directly opening projects this morning (as opposed to Studio first) the usual sdl project icon was visible. Maybe I made it worse by trying some other workarounds.

I'm currently copying projects, TMs etc. and will then try resetting / reinstalling Studio.

Thanks for the link above - I'll try that.