2003 Mail Merge

[KP]

I have just run detect and repair on my Outlook 2003. Now when I try to do a
mail merge from Word 2003 I keep getting the warning "another programme is
trying to send mail - do you want to continue" etc etc and I have to click
yes for every single message.

Normally I am sending 1300 personal messages as attachments to the members
of my association. I know you can turn this feature off in Outlook Express -
How do you turn it off in Outlook 2003?

Thanks