Please click "Show details" and post a screenshot again.

The most probable cause here is a corrupted project template.

If you used templates from previous versions of Studio, it is even very sure, that the problem is caused by the template.

Otherwise please try to follow the advices from this article to reset Studio: Repairing your installation of SDL Trados Studio

Please note that all of my existing projects suddenly became defective. They worked yesterday but they do not work today. There are no new projects based on templates from previous versions of Studio.

By the way, as I wrote I reset Studio using Freshstart but it didn't help.

OK, sorry–I have no more ideas. Something has gotten corrupt.

What I would do now: close Studio. Go to Documents - Studio xxxx - Projects and backup the projects.xml from there, then rename the file to projects.xm_ When done, start Studio. The project list will now be completely empty. Use "Open Project" command from the Projects view to open any of the projects  and try again. If that worked, open only the projects you need to work on now, do not load old, finished projects. If it does not work, close Studio again and restore the previous projects.xml–in that very case let us hope for someone from SDL/RWS.

Unfortunately, deleting the projects.xml file doesn't help.

I uninstalled Studio and installed CU13 instead of the latest version (CU14).

The problem has gone. All my previous projects work fine (incl. analyze and pre-translate).