So here is the problem. Connecting via webmail externally and trying to send an attachment 4 Meg doesn't do anything. Once the user clicks on Attach, the window is indicating "attaching" but never does anything. Looking at the traffic it looks like it uploads a bit of the file then just drops the connection. The message size limit is set to 200 Meg (was doing a message import and didn't want to run into problems) so the message size isn't a problem. Internally it works no problem for an 8 meg attachment. I've tried from IE 7, IE 6 and Firefox 3.