A corrupted Exchange Server database can be a result of network problems, database size issues, hardware-related concerns, log file corruption, and the most common, dirty shutdown. Actual solution to Exchange Recovery is dependent on the root cause of the problem, which can be analyzed by different ESE events of application log.
To narrow down these problems, consider the below events that might appear in application event log of Exchange Server:
Event Source: ESE
Event Category: General
Event ID: 901
<process name> (<process id>) <storage group name>Internal trace:<file name> (<number>)
The related database might or might not mount after you receive this event ID.
Event 901 can occur due to several reasons. It typically suggests that an unexpected error has been observed with ESE.dll, Store.exe (Information Store process), or Jet database engine. Not always, but one of the common problems encountered with event 901 is Exchange database corruption. You can sometimes detect this specific cause by an associated ESE Event ID 448 logging in the application log. However, when the issue is not Exchange store inconsistency, it can be simply resolved by restarting the Exchange store.
To isolate the depicted problem, you need to carry out the below sequence of steps:
Check whether or not application log includes an associated ESE Event ID 448
If ESE Event ID 448 is there in application log, perform the mentioned steps:
Check the system log for hardware, file system, or controller related issues. In case they exist, perform the corresponding actions such as, replacing the hardware, repairing the file system, and updating the system files.
If you can mount the database, use ExMerge utility to move all the mailboxes to a new, blank database and delete the corrupted database. But if you cannot mount the database, restore from the last online backup, run Eseutil /p repair, or apply a third-party exchange server recovery utility. Unlike Exchange Eseutil repair utility, an exchange recovery software can scan and repair the corrupted database using safe procedures.
One of the best applications is Stellar Phoenix Mailbox Exchange Recovery software. With support to MS Exchange Server 5.5, 2000, 2003, and 2007, this Exchange Server Recovery utility can restore all the mailboxes as separate *.pst file, while keeping the original database intact. In addition, the software can also recover deleted mailboxes.
Tips to Solve Event ID 901 in Exchange Server