Different options to resolve the problem with backlogged PRV files while using legacy agents (4262119)

There have been issues in past, eg. server was down, cluster failed over, Mail Target Agent for some reasons was not able to deliver the data.

Now all issues have been resolved, what can be done to process those accumulated PFV files?

-On target Agent Host, explore the share and find the folder for Mail Transmission Agent.
-Within, find the incoming folders from source servers.
-In each folder sort the PRV files by date, take the newest files and move them out to another folder (you can pre-create a folder with a unique name in advance, eg. SERVERNAME_BACKUP, in the same directory or in another directory and even on another drive)
-Move out all PRV files and leave only 10 or 20 oldest PRV files in the folder
-Repeat the procedure for all folders

The goal is to remove all files temporarily out of the queue so agent (MTA) can start processing the data instead of enumerating all the accumulated PRV files.

When files have been moved out start the MTA only, don't start the MSA or NTA because this will create and deliver new PRV files.

-Now you can start using the Service File Viewer to look up and control the queue.
-Verify MTA is working as expected, PRV files are being processed and they disappear from the queue.
-If MTA is working as expected start moving PRV files back to the original folder, sort them by date and move the oldest files first, move in small batches, 100-200 files.

-If this works as expected proceed and move 300-500 files, let the MTA process them and proceed adding the files.

-If for some reason MTA does not process the PRV files then you need to reinstall the MTA. This is a safe procedure and will not affect the migration, no data will be lost.
-Reinstall the agent and commit changes. Expand the target org, find the server, right mouse - properties - close with OK.
-Navigate to mailbox synchronization node - right mouse on the server pair - select "Reapply Agent Configuration".
-Now it is safe to start the MTA again.

Note:

Information about all PRV files is stored in the config.mdb file of the MTA, the config.mdb file is located in the same folder where the EMWMTA.log is located.

Often when files have been moved (or removed) from the folder they still appear in EMWMTA.log, MTA is still trying to process them but cannot find them.

Reinstalling the agent resolves the problem but the issue can be also resolved without reinstalling the agent.

The steps are:
-stop MTA
-find and rename the config.mdb
-On console navigate to Program Files/Quest Software/Migration Manager/Exchange Data and find there a file called EMWMTA.exe
-Copy this file to any computer (target agent host server is okay) and run the installation, when selecting the path select any folder (pre-creating a TEMP folder is a good idea), when install finishes open the folder and take the freshly create config.mdb file, copy it to the Mail Target Agents folder (instead of the old renamed config.mdb file).
-Navigate to mailbox synchronization node - right mouse on the server pair - select "Reapply Agent Configuration". This step will populate the config.mdb with correct updated information.
-Now it is safe to start the MTA again.