I had the same reply. I have VoIP. I moved the phone adapter behind my
wireless router and the problem was solved. Good Luck!

"allie h" wrote:

> I am connected to a wireless hub and keep getting this message when I try to
> send emails- have tried all sorts but no joy
> An unknown error has occurred. Subject '', Account: 'pop3.tiscali.co.uk',
> Server: 'smtp.tiscali.co.uk', Protocol: SMTP, Server Response: '554
> smtp.business.co.uk', Port: 25, Secure(SSL): No, Server Error: 554, Error
> Number: 0x800CCC6F