Disable Microsoft Replication Service Throttling

https://www.petenetlive.com/KB/Article/0001327

Problem

I had a problem recently during an Exchange 2007 to 2013 migration, (client can’t support 2016 yet!) Where the mailbox migrations were taking ages.

On the ‘Target’ server > Open ‘regedit’ > Navigate to;

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\MSExchange ResourceHealth

Locate the MRS REG_DWORD Value and change it to 0 (Zero)

Note: This wont take effect until the service is restarted, but don’t do that yet.

Edit the MsExchangeMailboxReplication.exe.config file, you will find it at the following location;

{Drive-Letter}:\ProgramFiles\Microsoft\Exchange Server\V15\Bin

Note: Run Notepad as administrator, or it might not let you save the changes!

Change the following settings;

MaxActiveMovesPerSourceMDB=”50″
MaxActiveMovesPerTargetMDB=”50″

ExportBufferSizeKB=”10240″

Below the line (above,) add the following (only if target is Exchange 2013 SP1 (Thats CU4!) and above);

ExportBufferSizeOverrideKB=”7500″

Change the following to 20 minutes;

DataImportTimeout=”00:20:00 />

Save and close the file.

Note: This wont take effect until the service is restarted, but don’t do that yet.

Execute the following command;

Set-MailboxDatabase “Target-Database-Name” -IndexEnabled:$False

Can I Restart the Mailbox Replication Service While Migrating Mailboxes?

For safety reasons I would say no, but yes you can actually restart the service during a migration, the individual moves then get flagged as;

StalledDueToMailboxLock

I simply left it for a while, and they all reverted back to ‘Copying Messages’.

When you have finished remember to re-enable indexing and throttling on the target datastore.