Hello Karolien, 
The just same problem has just happened to me and I wondered if you managed to resolve it. 
Thanks

Hi Dominic,
No, I didn't find any solution and didn't receive any useful answer. Please let me know if you figure something out!

Karolien Willems 

Hi Karolien,
The problem seems to have fixed itself.
I'm not sure if it's linked, but I noticed that it was fixed after I exported a bilingual file, made some changes, and reimported the file.

Hi Dominic,

Sorry for not answering earlier. I tried the exporting and reimporting but it didn't do the trick. I recently changed my pc and am now working in Windows 11, with the latest release of Studio. At first the problem seemed to be solved, but than it reappeared. I uninstalled and reinstalled several times, but in vain. If someone knows the solution of this riddle, I would be very grateful!!

Hi Dominic and Karolien, I am experiencing the same problem and none of the solutions proposed here seem to work. If somebody has another fix for this problem I would be really grateful if they could share it!

Hi Marloes,

This is the answer I finally got in another forum, the Trados Community Forum at https://gateway.rws.com/, selecting "Trados Studio Licensing Help":

A reset might help you with this.  To do this just close Trados Studio and then delete these folders:

%appdata%\Trados\Trados Studio\Studio18\

%appdata%\Trados\Trados Studio\18\

You will lose your plugins, and also your settings, but your projects and other resources will remain untouched. Putting the plugins back is trivial via the integrated appstore.

If you can't find these folders then you need to unhide your hidden files/folders:

www.howtogeek.com/.../

Then restart Trados Studio and see if that helped.

That worked for me. Once I had all my settings back as I wanted them, I made a back-up of the settings files, just in case it happens again (BaseSettings.xml and UserSettings.xml in C:\Users\*username*\AppData\Roaming\Trados\Trados Studio\Studio18).

I really hope this works for you too!

Hi Marloes,

This is the answer I finally got in another forum, the Trados Community Forum at https://gateway.rws.com/, selecting "Trados Studio Licensing Help":

A reset might help you with this.  To do this just close Trados Studio and then delete these folders:

%appdata%\Trados\Trados Studio\Studio18\

%appdata%\Trados\Trados Studio\18\

You will lose your plugins, and also your settings, but your projects and other resources will remain untouched. Putting the plugins back is trivial via the integrated appstore.

If you can't find these folders then you need to unhide your hidden files/folders:

www.howtogeek.com/.../

Then restart Trados Studio and see if that helped.

That worked for me. Once I had all my settings back as I wanted them, I made a back-up of the settings files, just in case it happens again (BaseSettings.xml and UserSettings.xml in C:\Users\*username*\AppData\Roaming\Trados\Trados Studio\Studio18).

I really hope this works for you too!