We were running Exchange 2000 on a Windows 2000 server. We added a new Windows 2003 SBS box and moved all of the Exchange 2000 e-mail accounts over to the SBS server. I just noticed that every user now has a new primary SMTP address. For example, all of our users were using firstname.lastname@example.org. Now, on the SBS box, everyone is using email@example.com. When I change the primary SMTP to firstname.lastname@example.org, it looks like all is good and then 5 minutes later it goes back to email@example.com . Any ideas? Thanks.