Troubleshooting JET_errVersionStoreOutOfMemory during a Mailbox Restore (4036053)

The Version Store keeps an in-memory list of modifications made to the database. In simple terms, the Version Store is where transactions are held in memory until they can be written to disk.  If something prevents the transactions from completing or writing to disk, this cache will be consumed and the store will stop responding to requests until there is space in the cache again.

Please note that when opening an Exchange Database (EDB) in Mailbox Restore, an ESEUTIL /R command is performed by default. Although this operation, which brings the database to a clean “down” state, commits the data in the logs to the EDB, it does not perform log truncation. Furthermore, ESEUTIL /R /T may truncate the logs, but will fail due to the JET_errVersionStoreOutOfMemory error.

To resolve this issue in Mailbox Restore, check the status of the EDB logs and, if there is a large number of logs present, perform a manual, off-line log truncation.

• Run the eseutil /mk <path to checkpoint file> command (i.e. eseutil /mkE00.chk).
• Look at the Checkpoint field in the output. For example, you should see something like this:
  • CheckPoint: (0x66805A, 7DF, 1C9)
  • The first number 0x66805A is the hexadecimal log generation number of the current log file.
• Create an empty folder (i.e. c:\tlogs).
• Copy all files with a log generation number higher than or equal to the current log file (i.e. E0066805A,E0066805B,E0066805C etc) to the new folder created in step 3.
• Note that all of log generation numbers are the hexadecimal. So please convert values to dec before comparison.
• Copy the following files to the same location:
  • E<prefix>.log
  • E<root.chk>
  • E<prefix>tmp.chk(i.e. E00.log, E00.chk, E00tmp.log)
• If E<prefix>.log does not exist, make a copy of E<prefix>tmp.log in the same folder and rename it to E<prefix>.log (i.e. E00tmp.log -> E00.log).
• Open the database using Mailbox Restore, pointing to the folder at #3 (i.e. C:\tlogs).

You should be able to see the mail items now and proceed with the restore.