I keep getting an Error 18 on email

[WPCentral Question]

When trying to send emails I have been getting Error 18 messages.
Have closed down a few times and tried again. Can send the odd email (some kept in Draft) but not all. Not sure how to update or re-install driver or which driver for that matter.

 

[ven07]

Are you attaching files? PC or phone? App or outlook program?