CTS Outgoing Mail Attachment Resolution
As of 3/28/2007, we have implemented a new server solely for our client to send mail, specifically mail with attachments.
Outlook:
Within Outlook, click tools -> E-Mail accounts -> View or change -> Next

Select
your account from the list by clicking on it, and click “Change...”
For Outgoing Mail Server (SMTP), using the following:
71.41.56.47

Click “More Settings ...”
Click the “Outgoing Server” tab
Put a
check in the box for “My outgoing server (SMTP) requires authentication”
Select “Log on using”
User Name/Password: Please call CTS or E-Mail
bill@ctsfla.com for the username and password
Place a check in the box next to "Remember password"

Click OK, then Next, and Finish
I would suggest exiting Outlook and re-opening to make sure the changes are applied properly.