To enable remote scripting for the service account, run the following command on the Exchange management shell for Exchange 2010.
Set-User mmsrvcacct -RemotePowerShellEnabled $True

New-ThrottlingPolicy –Name "Avaya_MM_ThrottlingPolicy" –RCAMaxConcurrency $null

Set-ThrottlingPolicyAssociation -Identity mmsrvcacct -ThrottlingPolicy "Avaya_MM_ThrottlingPolicy"

New-ManagementRoleAssignment -Name "Avaya_MM_ImpersonationRole" -Role ApplicationImpersonation -User mmsrvcacct

Set-ThrottlingPolicy -identity "Avaya_MM_ThrottlingPolicy" -RCAPercentTimeInAD $null -RCAPercentTimeInCAS $null -RCAPercentTimeInMailboxRPC $null