We recently moved all of our users over to new post offices. Every day or two I get a call about someone sending a message to a group (from their personal address book) or to some names that were in a personal address book (Frequent Contacts or other) and the complaint is that some of the recipients generate a D101 User Not Found or similar error. In most cases when I go to look at the details of the errant recipient it shows the address as being on one of the old post offices - user.oldPO.oldDomain, or similar. Not every internal recipient within a group held by one sender generates this error, and it's not always the same sender calling in the problem.

I've already gone through and synchronized all of the mailboxes. There is a switch that can be used in GWCheck named PABFix. Will this correct the entries in everyone's address books that are still pointing to the old post offices? Or is there another option?