Error message when I open a file in Editor: Object reference not set to an instance of an object

Hi,

I bought Trados 10 days ago and started getting this error message (Object reference not set to an instance of an object) a couple of days ago when I open a file in Editor, after I'm prompted to choose Source and Target languages and TMs, this message pops up in Editor. It seems to disable TMs and MT. 

I've tried to uninstall Trados and install it again. That didn't help. I've also tried the Repair button but that didn't help either.

Could you please help me fix this?