Illegal operation on closing outlook 2000

[tealc]

Hey,

I have the following problem :
I have a win98 with office 2000. Whenever I try to save and close a task or an item in calendar in outlook, outlook performs an illegal operation. This also happens when I close Outlook.
I have already tried to reinstall outlook and windows but it doesn't help.
Does anyone knows a solution ?
Thanks a lot

 

[doldol]

Try to delete in Delete items.

 

[tealc]

Thanks for your answer doldol but there are no items in deleted items so no luck with this.
Could it be a corrupt dll that's causing the problem? The big question here is which ddl and how can you detect it?