A month or so ago we had an issue with an exchange server where the recomended fix for the problem was to re-install IIS and re-install the CAS role. This fixed the problem but seams to have caused another problem as there no longer seams to be any replicas of the core System Folders. There are 2 Exch27k servers and I have tried the GuidGen route to reset the system folders, following AD replication I have shut down all the Exchange services and restarted and also dismounted the PF's and re-mounted but it never seams to re-build the System Folders on either server ? I am assuming I should see new SPF's with just one replica on the main server. They remain as the original ones with original contents and with no replica's. The server was a new build (not migrated from older version) but we did import some users from a 2003 environment and some from a Notes environment. Its sitting on 2003Srvr(64) How do I get a replica of the System Folders back ??