Originally Posted by killshot

I just helped some people i work for with this problem the other day
find the file your sent mail is in.. it has likely reached its maximum size almost 3 gigbytes i think...

and it doesn't matter if you have deleted the messages themselves... the file just continues to grow.

so when you send a file.. it is trying to put it in the sent mail folder before sending.. and it just gets stuck in the outbox..

Just delete the file.. and re-open outlook and it will create a new sent mail folder

Aside from that... outlook express isn't that great
if you must us a MS product.. try the regular outlook that comes with MS Office.