Large attachments get stuck on the server

I have a Lotus Domino 5.0.4 server on Win2k server 512 memory, and McAfee for virus scan. My problem is when a user sends an e-mail with a big attachment, my other e-mails get stuck on the server. Do you have any suggestions for me?
You could try multiple mailboxes, or more delivery threads. I can't give you a definite answer based on the info given here.

This was first published in April 2002