Hi Asyn,
Unfortunately the problem has come back after I logged back on.
I have had to go into Menu / Settings / Protection / Core shields / Mail Shield
to untick "Scan inbound emails (POP3, IMAP4)" and " Scan outbound emails (SMTP)"
and it will now send and receive all emails all OK. I tried to repair AVAST again with the same results.
Any other suggestions?
Regards,
David