Do you mean the file has an extension of .tmp?
When you save a file, excel will save it as a temporary file (8 characters, no
extension). Then if that save is successful, excel will delete the original and
rename this funny named file to the original's name.
If something interferes with the save, then you might see this temporary file
left behind (but excel gives you an error warning, too).
But I've never seen excel save a file as .tmp.
A little while ago, someone else posted the same kind of question. Guesses
included a macro that was trying to help, an antivirus program misbehaving, or
even some kind of GoBack utility that windows is running. (I guessed GoBack,
but I don't know if that's close to how it works.)
So if you're getting the .tmp files, maybe you could delete it, then open excel
in safe mode:
close excel
windows start button
Run
excel /safe
to see if you can eliminate the macro suggestion. (safe mode stops macros from
running.)
If you find the answer, please post back.
