We started receiving this error for all our users this morning and from everything that I have read, it has to do with the Global Address List or the Offline Address book. A number of solutions include rebuilding the GAL, which is what I am trying to do. However, we are running Exchange 5.5 and I can not for the life of me find how to do this. I've been through Microsoft Exchange Administrator and I can't seem to find an option on rebuilding the GAL. So my question is, how do I rebuild the GAL for Exchange 5.5? Our users are running Outlook 2003 clients.