In an attempt to squash Viruses and Trojans from using your Email Client to send SPAM, Qwest (as well as Comcast) has disabled Port 25 causing some email clients to fail when trying to send email. If your experiancing a send error, (Cannot Connect to Server) you'll want to change the Outbound SMTP Port from port 25 to port 587.
Here is how to fix this issue for Outlook:
Go to Tools / Account Settings
Modify / Edit the account you are having issues with