Entourage error: Recipient <name> lacks host part

My google fu is weak as I can’t find this error message and I’ve never use entourage before.

Someone trying to send mail to a user in one of the companies I support is getting this error message. As far as I can tell the mail is being received at our end and there are no other general issues that I can see might be causing the problem.

I can’t find this error message which appears in the error log (mac general or entourage specific I’m not sure) and I’ve checked what would appear to be obvious things like they have the full, correct email address stored.

Apologies if this sounds a bit vague, I’ve got a single screen shot of the error message and am being relayed from one (non technical) user to another in a different company.

If it has any relevance, we’re using a hosted exchange service which otherwise seems to be working correctly.

Any ideas?

Do you have Outlook Web Access running, and does the message show up there?

As far as I’m aware the mac user is the only person getting an error sending into our mail service. Outlook Web Access is running but we’re not getting errors internally.

The user getting the error is external to our organisation sending email to us.

Right, but if the user logs in via the web, does the message show up there?

sigh the joys of the mysteriously disappearing error. While I’m happy the problem’s gone, I’d have liked to have know what might have been the cause.