When FP publishes a page it uploads to a .tmp file, then renames the
..tmp file to the correct file name.
There are two possible reasons for the error message:
1) You have used your space allocation, or the disc on the server has
no free space. (Note that FrontPage needs some work space within your
allocated space.)
2) There is a permissions problem in your site - the extensions need
to be checked and possibly re-installed.
Based on previous posts, the first error is most likely.