A few days ago I finally fixed a problem I had been having with my Sprint HTC Touch Pro. For some reason (an update I assume) I was still able to get mail messages, but not able to send any. I would get some error message. I let it go for days, until finally finding the fix. Just click the link below and solve your issue.
In my opinion Sprint should send out emails telling users how to correct these issues, rather than the user having to figure it out ourselves.
You're welcome!
Download details: WM 6.1 Hot Fix for Sending POP and IMAP E-mail .