Office 2010 Migration - Outlook

Whilst my office suite (2010) seems to have migrated well, has anyone had any issues with sending mail from Outlook.
I have a exchange server account in Outlook which works fine, however I also have a BT Internet (Yahoo version) pop 3 account, which is set to the correct settings. However, this account receives ok on port 110, and also when sent a test message from port 25, it works and comes back fine. However, when I actually send a real message, the smtp will not send, which seems strange. Port 25 is the correct setting as email is same as service provider.

Thanks for that. Yes, I ran elevated SFC /SCANNOW, after 100% mark it reported 'resource protection found corrupt files and repaired'. CBS log too long to read. But on reboot and running Office 2010, error corrected and mail can again be sent. Regards Mike

Just for info sfc repaired two files:
C:\windows\syswow64\en-us\mlang.dll.mui and windows.speech.uxres.dll.mui
not sure how relevant to Outlook but now fixed. Guess running sfc kicks a few things as it goes :)
M