Cannot save files, not even as copy with new name

We are having problems with saving files from DesktopEditors in Windows.

Trying to save the file at its old location, I get an error message: The file could not be written, it is either write protected, opened in another application or write access to the storage is generally not possible.

Well, write access to the storage is possible. There is space enough, permissions allow writing and writing is possible through other applications.
The write protection (NTFS attribute) is not set.
As much as I can tell, the file isn’t opened in another application. E.g. I tried saving from OnlyOffice DesktopEditors as first action after full reboot. There is no indexing or virus scanning apart from those built into Windows.

The most strange thing is that, now, trying to save the file via “Save as” in another location and/or under a new name, I get the same error message as before.
OS: Windows 10, Windows 11
Application Version: 8.1.0, 8.3.0, 8.3.1

I tried searching the Windows event log and the debug mode of DesktopEditors without finding anything related.
I also tried the MS SysInternals applications handle.exe and handle64.exe to see whether another application holds the file open, but it didn’t show anything. (Not even the OnlyOffice DesktopEditor in which the file was opened, obviously.)

I’d be glad about any hint and help you could give me. Thanks in adveance!

Hello @zazara

What is “storage” in your case? It is your hard drive/SSD?