ErrorExceededConnectionCount

Problem

You may get this error when more number of mailboxes are being migrated which establishes more number of connections to Exchange server or when more number of messages processed by it.

Solution:

Message throttling: Group of limits that are set on the number of messages and connections that can be processed by an Exchange server. These limits are required to protect an Exchange server from being flooded with messages/connections. However you can change the default settings to match your requirements.

• Open the Exchange Management Shell.
• Enter the the below command:

  • To get the current allowed number of concurrent connections per use

    Get-ThrottlingPolicy | Format-List -Property Identity, EWSMaxConcurrency

  • To increase the value of allowed number of concurrent connections per user on Exchange Server 2010 machine:

    Set-ThrottlingPolicy -Identity DefaultThrottlingPolicy* -EWSMaxConcurrency $null