Deleting large emails take a long time in shared email folders

I manage several email accounts in outlook 2003. I have a personal account
and 3 shared email accounts. About 4 weeks ago, I noticed that I can delete
large files in my personal account without any type of delay. When I attemp
to delete a large email (500 Kb+) there is a drastic delay in the amount of
time to delete the email. Example a 3Mb email can take up to 3 minutes to
delete in the shared email account and about 3 seconds in my personal account.

I am able to delete without any type of delay on other computer on the
network.

I have verified the settings, removed and reinstalled outlook, cleaned up
all of my archive folders. nothing seems to be work. I have not installed
any new software on my computer.