G'day hope someone can help........

I have an WIN XPSP2 using MS Office 2K3 Outlook SP2 as the default
email editior (using a POP3 mailbox) all MS updates have been installed
and configured.

However whenever i forward an mail with an attachement I recieve a "550
relaying mail to" [domain] "is not allowed".

I can create a new copy of the original email, attach the original
attachment and the email is successfully delievered.

FYI - My ISP hosts is also my mail host.

I'd appreciate any assistance

With Regards

Alchemy