After running an offline information store restore, but before starting the information store service, run the isinteg -patch command.
During startup, Microsoft Exchange Server validates a globally unique identifier (GUID) in the information store with an entry stored in the Windows NT Registry and the Microsoft Exchange Server directory. The information store service cannot be started if the GUIDs do not match in each of the three places. Mismatches can occur if the information store has been restored from an offline backup.
If a copy of the information store (Pub.edb and Priv.edb) is restored from an offline backup and isinteg -patch has not been run, it fails and a -1011 error is generated when the service is restarted. The -1011 error produces an entry in the Windows NT Event Viewer Application Log with source ID 2048. The error message reads as follows: "The information store was restored from an offline backup. Run isinteg -patch before restarting the information store."
This error occurs because the GUIDs used by the information store that was restored are old and matching GUIDs might already exist. The GUID for this restored information store must be replaced to ensure that it is unique.
An error message, DS_E_COMMUNICATIONS_PROBLEM, will also appear.
When run with the Patch option, ISINTEG resets the entries for the GUIDs in the database, directory, and registry. It also patches information used during replication to prevent incorrect backfilling. After it has been patched, the information store service can be started again.