So far all complaints about intermittendly inaccessible files had to do with one or more local reasons:
- File is stored on a NAS -> slow access and simultaneous access from other users/programs -> create a local copy
- Win7 is the OS -> very picky in respect to access rights and ownership -> make sure MP3tag user is the same as file owner
- File gets opened via the context menu of Windows Explorer -> open with the functions of the MP3tag File menu
- WMP is open at the same time and tries to gather information about the currently processed file -> close WMP
It is now up to you to investigate your workflow if any of these possible interferences apply
This, by the way, would have been mentioned in the subsequent thread
mp3tag hangs in Windows 7 64bit
Only that the first mentioned thread would have added more context.
What would also interest me: how did you check that your files are not corrupted.