Enterprise Vault (EV) PST migration fails with the following error: "Migration of PST <PST file path> exception"

Problem

Enterprise Vault (EV) PST migration fails with the following error:

Error Message

Failed to read PST Policy record for Mailbox id: Error: Exception from HRESULT: 0x80005000

Cause

This error occurs due to duplicate entries in the ExchangeMailboxEntry table in the EnterpriseVaultDirectory database, which may result from past Exchange migrations.

Solution

To check that this is the case and resolve the issue, follow the steps below:

1. Run the following query on the SQL server hosting the EnterpriseVaultDirectory database:

Use EnterpriseVaultDirectory
SELECT *
FROM ExchangeMailboxEntry
WHERE (MbxAlias LIKE '%yourusername%') - replacing yourusername with the appropriate mailbox alias for the affected user

If the query finds more than one entry for the user, the duplicate entries need to be deleted (usually the duplicate entries will have a "%MARKED%" entry in the LegacyMbxDN column).
Note: Before making changes to any EV database, ensure you have carried out a full backup as per usual backup procedures.

2. Take note of the value in column ExchangeMailboxEntryID for both entries

3. Run the following query to delete the duplicate entry:

Use EnterpriseVaultDirectory
Go
Delete from exchangemailboxentry
WHERE (LegacyMbxDN LIKE '%MARKED%')

4. Run the following query twice each time using the value from Step 2 until one of them returns a result:

Use EnterpriseVaultDirectory
Select * from PSTFile where ExchangeMailboxEntryID = 'value from step 2'

5. Take note of the value in the MigrationStatus column.

6. If the query returns an entry with the invalid user, it will need to be modifed using the query below.  If it is the correct entry, skip to Step 7.

Use EnterpriseVaultDirectory
Update PSTFile
Set ExchangeMailboxEntryID = 'valid user id from step 2' where ExchangeMailboxEntryID = 'invalid from step 2'

7. Run the query below to change the MigrationStatus.

Use EnterpriseVaultDirectory
Update PSTFile
Set MigrationStatus = 800 where MigrationStatus = value noted in Step 5

8. On the EV server, Add a new DWORD registry key to prevent this problem from occurring in the future.

HKEY_LOCAL_MACHINE\software\KVS\Enterprise vault\agents\SynchInMigrationMode=1.

This registry key was introduced in EV 6 SP3, and forces EV to automatically assign migrated mailboxes to existing archives using the legacyMbxDN value.

9. Re-start the EV Admin Service after changing the registry key above.

10. Synchronize the user's mailbox.

11. Run the query from Step 1 to confirm there is only one entry found.

12. Re-start the PST Migrator task.

Warning: Incorrect use of the <Windows registry> may prevent the operating system from functioning properly. Great care should be taken when making changes. Registry modifications should only be carried-out by persons experienced in the use of the registry editor application. It is recommended that a complete backup of the registry be made prior to making any changes.