Cant save files. Get write error.

After bringing files from my windows 7 computer to my new windows 10 computer and editing them, I cant save them. Keep getting "error saving the domument xxxx. Write error The file could not be written. I get this error no matter where I try too save it or if I use save as etc.
Using version on both old and new computer. Even tried save it back to the thumb drive I brought it over from using a new name.

This is probably a Windows Permissions problem. Right-click the containing folder, select Properties and check ownership. Change ownership to current user, with “apply to sub-items” checked.

New files I create can be saved.

I have no problem with any other program and it wont even save to my thump drive.

I have the same problem. Afraid of loosing several open files. Version: (x64) OS=Win 8.0 64bit
Problem is not Windows Permissions. Using Task manager CTRL+ALT+DEL force close LibreOffice and restart. For me all files recovered. Then able to save anywhere usual without reboot of OS or changing permissions.