Mail Agents occasionally stop processing PRV files (4212049)

Restarting the Mail Target Agent (MTA) or Mail Source Agent (MSA) may help only temporarily. There are frequent errors of the form:

"10/21/2015 12:28:23 PM CDatabase::Execute Error 3035 System resource exceeded."

or 

"Error 3800 Name is not an index in this table.
10/21/2015 9:58:49 PM CReceiver::AddFile Error 3407 Server NAME was not found in the database"

This can be caused by local mail, calendar, PF or FB agent's Config.MDB database corruption.  Also there may be a particular issue when working with the large subsets of data in MS Access MDB files.  Please refer to the resolution section for more details.

The following is the list of workarounds that can help to resolve this problem:

1. Commit changes if the changes are not committed.  If the changes are committed make a small but not significant change and commit the changes again.
2. Open the properties of the target server within the console and click OK.  This will update the MDB file and the config.ini for the mail target agent.
3. Navigate to the properties of the Exchange server under Source or Target Exchange organization in QMM project manager and set memory on the corresponding agent to 128000kb.  This is the default setting and the only configuration where the agent can flush the memory and fully recover automatically.

NOTE:  If the limit is set and the agent's process reaches it, the agent just restarts itself to free up the memory used and continues to synchronize mailboxes (or public folders) from the point it has stopped at.  At that moment the following error is logged which is considered normal agents behavior:

"The agents system memory limit 128000 Kb has been exceeded.  Agent will be terminated."

4. Reinstall the corresponding agent.  When reinstalling ensure agents folder that contains local CONFIG.MDB file is removed.  Its located under Aelita Exchange Migration Wizard shared folder on Exchange server where the agent is installed. For example:

C:\Windows\SysWOW64\Aelita Exchange Migration Wizard\Mail Target Agent\Config.mdb

IMPORTANT:  Please also rename (if present) the corresponding agents tracking database on the root of drive where it's installed.  In this case the issue would be normally caused by corruption of the agent's tracking database and a new one will be created upon the agents' install.  The tracking databases are:

For mail the file is in root of the disk where agent is installed - EMWST.DAT
For Public Foldershttps://support.quest.com/kb/SOL21481 the file is in root of the disk where agent is installed - EMWSTP.DAT
For Free/Busy Agent file is in the root of the drive where agent is installed - EMWFBSA.DAT
For Calendar the file is in same folder as agent is installed - EMWSCSA.DAT, if two-way sync then there is second file - EMWTCSA.DAT

This indicates presence of some process in the environment that keeps corrupting agents database while its open for read/write operations.

It is strongly advised to exclude the entire Exchange Migration Wizard or Quest Migration Manager folder shared as qmmex$server_name$ as well as agents tracking databases located in the root of drive from the scope of any backup and/or anti-virus tools.

5. In several cases it was noticed that backup software replaces some MDAC dll files with its own versions.  This causes corrupted agents MDB files.  Please re-install MDAC on the server where this error is experienced.
6. If none of the above actions help it is possible that config.mdb file of the Mail Target Agent is constantly getting corrupted.  This may be due to an issue within Microsoft Jet engine.  Please refer to this Microsoft KB article: http://support.microsoft.com/kb/286153
a. Stop Mail agent before modifying the registry.
b. Apply the described procedure on the Exchange server where Mail Agent is running.
c. Copy config.mdb file from another working Exchange server where Mail Agent is running and perform step 2 above.  If there is only one target server in the environment please reinstall Mail Agent.

Note:  After reinstalling the Mail Agent it is important to Commit Changes and update the configuration files as described in step 2.