This is the actual error: An unknown error has occured. Protocol: SMTP, Port: 0, Secure (SSL) : No, Error Number: 0x800C13B.
howerdjay - a possible cause is that your 'Sent Items.dbx file is damaged'
1. Click START, point to FIND, and then click FILES OR FOLDERS
2. In the NAMED box, type SENT ITEMS.DBX
3. In the LOOK IN box, click your primary hard disk (usually drive C), and then click FIND NOW
4. Right-click the SENT ITEMS.DBX file, and then click RENAME
5. Type SENT ITEMS.OLD and then click OK
6. Restart Outlook Express. This action automatically creates a new Sent Items.dbx file