This might seem like an obvious question... but, have you rebooted since the
problems began? Also... was anything installed recently? In particular,
Office 2003 SP2 became available this past week. All of our computers were
automatically updated. Any chance that yours was as well, and that this
might've precipitated the problem? I.e., if SP2 *was* installed, when was
the last time Excel ran without a problem (I know you encountered the
problem today... but if SP2 was installed this past week, had Excel been run
successfully since installing SP2).

--
Herb Tyson MS MVP
Please respond in the newsgroups so everyone can follow along.