The file name you entered was not a valid DOS file name.
For example, the file name may contain invalid special
characters, or may have trailing or leading spaces,
may have more than eight characters before the period,
or may have more than three characters after the period.
 
You may also be attempting to save the file on a
nonexistent drive or path.
 
Enter a valid DOS file name (up to eight characters,
followed by an optional period and an optional
three-character extension.) Make sure there are no
trailing or leading spaces.