Can't send email - 'Test Account Settings" fail on email address

Using Outlook 2002. Had Outlook 2003 installed and removed. Since then, I
have not been able to send or receive email. Did all the basics including
creating a new pst file.

When I run the "Test Account" feature, everything tests out fine except for
the email address. I get the error message "...unable to send test
Message. Please verify the E-mail address field."

I have done so and retyped the email address several times with no success.
By contrast, I entered the same information into Outlook Express and it
retrieves the mail immediately.

Would appreciate some help...

Thanks