Excel .exe has generated errors

[John]

I have a user that receives the following error when he
opens and trys to save the file aftering making changes.

Excel.exe has generated errors and will be closed by
windows. You will need to restart the program.

It only happens with the same file. He can open and
making changes to any other excel file without a problem.
Other users can open the file and make changes but for
some unknown reason this user can not.

Any ideas?

Thanks,
John