553 sorry, that domain isn't in my list of allowed rcpthosts (#5.7

[Guest]

OS: XP, Outlook 2002 Sending from Outlook I get this message. When I send
email directly from webmail there is no problem sending to the address that
gets rejected.

 

[Lanwench [MVP - Exchange]]

OS: XP, Outlook 2002 Sending from Outlook I get this message. When
I send email directly from webmail there is no problem sending to the
address that gets rejected.

Are you authenticating properly to your SMTP server in your account
properties? If so, and this is only for one domain/address, contact your
ISP.

 

[BillR [MVP]]

I'd say your server is rejecting it and you dont' have control over it.
Consult your system administrator.