Activation showing correct but still cant send email after updating to Windows 8

I can receive emails fine but currently when I try to send a test email it comes up with an error…

Cannot send message “5.1.0 Authentication Required”

I have deactivated and reactivated with the code that was emailed to me.

Does anyone know what has gone wrong?

Hello,

are you sure that you are using correct login and password for your email account?

with regards
Jan