haertig, I am not a tech genius. I mostly ask someone else to configure the computer and I just use the applications in a simple manner.

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Do you possibly have one of these applications running, intermittently/on demand, and your seemingly random issue is related to this application running/not running, and not to a specific Word document?


In most cases, I work on Word or Excel one at a time.
Sometimes I open two or three Word files. But mostly one at a time.

Yes, I do multitasking sometimes, when I run Realplayer Downloader to download some You Tube videos while I am working on Word files. But it seems to me that has nothing to do with the problem because :

a) it is the same when I open the Word file and write next time
b) it is always the same Word files where Ctrl functions are paralyzed, and same Word files where Ctrl functions are still working.

I am thinking of making an experiment, copying one "OK file" into a blank page and saving it as a new file, and doing the same to an "not-OK" file. Then I will see if the new files inherit the same original problem.