Exchange Server 2013 and 2010 have a default throttling policy which restricts user accounts to no more than 20 open connections to the server. This restriction on the Vault Service account would cause failures of the Enterprise Vault tasks that run under the account. To prevent these failures, you must remove the restriction from the Vault Service account when you archive from Exchange Server 2013 and 2010.
Enterprise Vault includes a PowerShell script called SetEVThrottlingPolicy.ps1 which creates a new policy and assigns it to the Vault Service account to remove the restriction. You must run SetEVThrottlingPolicy.ps1 against an Exchange 2013 or 2010 mailbox. If your Vault Service account already has a mailbox on Exchange Server
2007 or earlier, you must first move the mailbox to Exchange 2013 or 2010.
However, in certain circumstances it may be problematic to create and assign this policy via the powershell script provided. In those situations the below commands can be manually run to create and assign the policy to the Vault Service Account mailbox.
.\SetEVThrottlingPolicy.ps1 -user domainname\vsa -server EX2013-CAS.EV.Local
— After running the command if it is asking for user name & password
Please use exchange server credentials, using that currently you are logged in.
Example : domainname\exchangeadmin and password = *******
in my case i had issue with archving where the task was unable to archive item with the error Lie Mode Lock