When a database is corrupt or damaged, data can be restored from backup or repaired using Eseutil. Eseutil is a command line utility that works with Extensible Storage Engine (ESE), database (.edb) files, streaming (.stm) files, and log (.log) files associated with an Information Store, in a given Storage Group.
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Technorati : Database Utility, Exchange Server, Guide
Del.icio.us : Database Utility, Exchange Server, Guide