It sounds like you have a problem with one of the workbooks/addins that loads
each time excel starts.
Next time you start excel, go into Tools|Addins and uncheck all the options
(keep track of which were checked).
Also, move all the files out of your XLStart folder
(use windows start button|Search to find that folder, and keep track of these,
too).
Then restart excel and test it out.
If it works ok, then start adding things back one at a time. And restart excel
after each time.
When you find the thing that's causing the trouble, you have to determine what
it is and if it can be fixed.
(If it's an in-house project, find that developer and show him/her what's
happening.)
Chip Pearson has some notes on how to diagnose startup errors at:
http://www.cpearson.com/excel/StartupErrors.htm
And Jan Karel Pieterse has more notes at:
http://www.jkp-ads.com/Articles/StartupProblems.htm
