Hello Peter Peters ,

First of all, I believe there are a couple of seperate issues here but first things first.

It is essential that everything is up to date (Windows/Studio/MultiTerm/Drivers etc)

Please take a look at the following Wiki- and follow through on both parts

https://community.sdl.com/product-groups/translationproductivity/w/customer-experience/3392/how-to-part-1-trouble-shoot-unexplained-errors-and-unwanted-behaviour-in-studio-multiterm

(you may need to run the Windows updates at least twice until they are properlyy installed.

Also take particular attention about adding Studio (and MultiTerm) to your AntiVirus 'White list' and reboot your PC after completing all the updates.

Next I would be taking a look at the problematic files-

as you state-

Peter Peters said:

I worked many times before with Trados even with much bigger files without having this problem.

this may suggest there is actually a problem with these particular files.

What happens if you take the individual files as a single file translation and immeadiately save target as  without doiing any translations?

Hi Steven

Thank you for your fast reply.

I can confirm all is up to date. I have a second computer with Trados 2019 installed for emergency reasons:

HP Windows 7 (the Thinkpad is Windows 10 Pro) 12 GB Ram, 1 Samsung SDD, CPU i7 6th generation.

I transfered the project there and had no problems with saving the files.

Finally I found out that the TM in the original project was damaged and after I have removed it the saving problem was solved.

But the problem with the right mouse button and copy and with CTRL F remains on both computers with all files and can only be solved when I open another file in edit mode and switch to and back.

Thank you for your help

Peter