Exchange Client Throttling

NOTE: This section is ONLY valid for Exchange 2010 or higher.

NOTE: As an alternative to these instructions, DigiScope® includes the DigiScope® Administrator Account Setup Tool, which will automatically perform all of the manual setup steps outlined here.

ATTENTION: DSAdmin Username Change
Previous versions DigiScope utilized an account just named "DSAdmin" and a throttling policy named "DSPolicy".  To better support the different permissions requirements of different versions of Exchange, we have changed the recommended names to be Exchange-version specific, as in "DSAdmin2013", "DSAdmin2010", "DSAdmin2007", etc.

When following these updated instructions, please substitute your matching Exchange version number wherever it says "DSAdmin{ExchangeVersion}" or "DSPolicy{ExchangeVersion}".  (For example, on Exchange 2010, use "DSAdmin2010" and "DSPolicy2010".)

Modern versions of Microsoft Exchange use a default Client Throttling Policy that implicitly governs and limits the bandwidth that each Microsoft Exchange user consumes within an organization.  These default limits are not acceptable for DigiScope® operation, so a custom Throttling Policy named "DSPolicy{ExchangeVersion}" must be created and assigned to the DSAdmin account and all other members of the "DSAdministrators" group as outlined below:

In the example below, we are adjusting the settings for the Windows account named DSAdmin{ExchangeVersion} and creating a throttling policy named DSPolicy{ExchangeVersion}.

  1. Open the Microsoft Exchange Management Shell and run the following commands:

    1. New-ThrottlingPolicy DSPolicy{ExchangeVersion}

    2. Set the policy using the appropriate command for your Exchange version:

      • Exchange 2010
        Set-ThrottlingPolicy DSPolicy{ExchangeVersion} -RCAMaxConcurrency $null -RCAPercentTimeInMailboxRPC $null -RCAPercentTimeInCAS $null -RCAPercentTimeInAD $null -CPAMaxConcurrency $null -CPAPercentTimeInCAS $null -CPAPercentTimeInMailboxRPC $null -CPUStartPercent $null

        STOP: If you are running Exchange 2010 RTM/SP0, the above command will not work properly; therefore you will either need to patch the server to at least SP1 or replace the above command with the following:

        Set-ThrottlingPolicy DSPolicy -RCAMaxConcurrency $null -RCAPercentTimeInMailboxRPC $null -RCAPercentTimeInCAS $null -RCAPercentTimeInAD $null -CPUStartPercent $null

      • Exchange 2013 - 2016
        Set-ThrottlingPolicy DSPolicy{ExchangeVersion} -RcaMaxConcurrency unlimited -RcaMaxBurst unlimited -RcaRechargeRate unlimited -CpaMaxConcurrency unlimited -DiscoveryMaxConcurrency unlimited -DiscoveryMaxMailboxes unlimited -DiscoveryMaxKeywords unlimited -DiscoveryMaxPreviewSearchMailboxes unlimited -DiscoveryMaxStatsSearchMailboxes unlimited -DiscoveryPreviewSearchResultsPageSize unlimited -DiscoveryMaxKeywordsPerPage unlimited -DiscoveryMaxRefinerResults unlimited -DiscoveryMaxSearchQueueDepth unlimited -DiscoverySearchTimeoutPeriod unlimited

        STOP: If you are running Exchange 2013 RTM/CU0, the above command will not work properly; therefore you will either need to patch the server to at least CU1 or replace the above command with the following:

        Set-ThrottlingPolicy DSPolicy -RcaMaxConcurrency unlimited -RcaMaxBurst unlimited -RcaRechargeRate unlimited -CpaMaxConcurrency unlimited -DiscoveryMaxConcurrency unlimited -DiscoveryMaxMailboxes unlimited -DiscoveryMaxKeywords unlimited -DiscoveryMaxMailboxesResultsOnly unlimited -DiscoveryPreviewSearchResultsPageSize unlimited -DiscoveryMaxKeywordsPerPage unlimited -DiscoveryMaxRefinerResults unlimited -DiscoveryMaxSearchQueueDepth unlimited

    3. Get-ThrottlingPolicy -Identity "DSPolicy{ExchangeVersion}"

      • Running the above Get-Throttling command will list out the configuration for the policy. Be sure to review it to ensure that all settings are as desired.

  2. For all accounts that are members of the DSAdministrators group, you need to need to assign them the DSPolicy by executing the command below. Replace the Account parameter with name of the specific account:

  3. To validate the policy assigned an account and review each parameter execute the command below. Replace the Account parameter with name of the specific account you want to check:


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