Outlook multiple send/receive

My problem is in Outlook 2002, normally if i send a small message it sends without any issues, but if i send an e-mail with a large attachmet(2 MB or larger) Outlook continually sends and receives until i’ve got a list of up to 12 send and receive tasks in the details box. if i cancel the extra tasks and go back to the original message task it says that 100% is complete but the message doesn’t budge out of the outbox no matter how long i wait. I’ve gone into the send/receive settings to make sure I wasn’t set up to automatically send/receive every minute or so and it wasn’t. If anyone has come across this in the past or knows the cure it’d be greatly appreciated. My system is Win2k SP3 and Office XP PRO.

Regards