Try port 465 instead of 587 as per:
http://mail.google.com/support/bin/a...y?answer=13287
"Red Stripe" <> wrote in message
news:7741A6B9-50AA-4043-840B-...
>
>
> An unknown error has occurred. Subject 'New e-mail / address information',
> Account: 'GMAIL', Server: 'smtp.gmail.com', Protocol: SMTP, Port: 587,
> Secure(SSL): Yes, Error Number: 0x800CCC0B