Typically, damage to library databases (dmsh.db and others) can be repaired using the database maintenance tools provided in ConsoleOne or using GroupWise Check (GWCheck). See Maintaining Library Databases and Documents and GroupWise Check.
If damage to the library is so severe that rebuilding databases is not possible:
Stop the POA that services the library. See Stopping the POA.
On NetWare, use a Target Service Agent (GWTSA or TSAFS) with a supported backup program or your backup software of choice to restore the library. See Target Service Agents.
or
On Linux or Windows, user your backup software of choice to restore the library.
Restart the POA. See Starting the POA.
To update the restored library databases with the most current information stored in other post offices, run Analyze/Fix Databases with Contents selected. Also run Analyze/Fix Library. See Analyzing and Fixing Library and Document Information.