The backend is GW 8.0.2, clients are GW7.0.4, although I don't think the problem is client related. We recently made two changes:

1. Changed the preferred SMTP domain name from to (examples, obviously)
2. Changed the preferred address format from User ID@Internet domain name to First Name.Last Name@Internet domain name

The second change introduced two issues that had to be manually addressed - removal of spaces and ambiguity due to users with the same first and last name. I addressed both of these by going to GroupWise|Internet Addressing, clicking Override next to Preferred Address Format and manually entering a Preferred EMail ID so Johann von Scott became instead of Johann.von, and adding a middle initial for duplicates so that the second John Smith became

We've got two users who are now receiving mail from Internet senders that is intended for a different user. It's not 100%, either - sometimes the mail goes to the correct mailbox, sometimes not. And it's not that they're swapped - user 1 may get some mail intended for user 2, but user 2 doesn't get any mail intended for user 1. The user's names are not similar (one is "Mary Jones" while the other is "John Smith", for example). They are in the same post office, and both users needed to have their Preferred Mail ID entered manually. They have unique FIDs.

Everything looks right with the mail - it just gets delivered to the wrong mailbox. The users do not have proxy rights to each other's mailboxes. There are no rules that would forward messages to the user getting them by mistake, and the message never arrives in the correct recipient's mailbox. The inbound GWIA log shows it is addressed to the correct user, and once it's in the system, I don't know how to do trace it any further. Is there a message tracing tool I can use?

My suggestion - for testing purposes only - is to move one of the users to a different post office, in a different domain, but that shouldn't be necessary.

I cannot find any references to this happening before. Anyone else experiencing this?