Month: July 2011

RTCP active calls must be false if bypass is enabled and refer support is disabled Error


In Lync Server 2010 While configuring a trunk to enable media bypass, and disable (un-enable) the refer support (as the recommended settings when creating a SIP trunk to Cisco Unified Communications Manager CUCM), you may receive the below error when you try to commit changes:

RTCP active calls must be false if bypass is enabled and refer support is disabled





As the error message mention, RTCP active calls must be false if bypass is enabled and refer support is disabled,

RTCP active calls can’t be modified from the Lync Control panel, you need to open Lync management shell to configure it as false


in the below example, my Trunk name is: PstnGateway:

– in the trunk prosperities, Temporarily un-enable the media bypass, and commit to save changes:




– Now, let’s open Lync Management shell and check the status of RTCP Active Calls, and RTCP Calls on hold:

Get-CsTrunkConfiguration -Identity PstnGateway:


We see both are True by default, Also note the EnableSessionTimer status is False.

– Now, run the below commands to set RTCPActiveCalls and RTCPCallsonHold as false:

Set-CsTrunkConfiguration –identity PstnGateway: –RTCPActiveCalls $false –RTCPCallsonHold $false

You will be prompted to set EnableSessionTimer as true, to do so, run the below command

Set-CsTrunkConfiguration –identity PstnGateway: –EnableSessionTimer $true



– Now lets check the status again:

Get-CsTrunkConfiguration -Identity PstnGateway:


Now you can Enable Media Bypass on the Newly Created Trunk


Commit to save, and it should complete successfully this time


How To Know Microsoft iSCSI Initiator Version

I’ve been through a troubleshooting that I needed to know what is the version of iSCSI initiator is running on the server (we may come to the issue and the troubleshooting done in another post)

If you are in the same situation, you can use the steps below to identify the version of iSCSI initiator on your server:


STEP1: Find the Driver Version Number

– Open Device Manager, and expand the SCSI and RAID controllers node


– Right click on Microsoft iSCSI Initiator, and click Prosperities

– Go to the Driver tab, and take note of the Driver version number



STEP2: Map the Driver Version to the iSCSI Version

– lookup the version number in the below table to find the corresponding iSCSI Initiator release version:


Driver Version iSCSI Initiator Version
5.2.3790.198 version 1.0
5.2.3790.205 version 1.01
5.2.3790.215 version 1.02
5.2.3790.218 version 1.03
5.2.3790.243 version 1.04
5.2.3790.244 version 1.04a
5.2.3790.277 version 1.05
5.2.3790.279 version 1.05a
5.2.3790.302 version 1.06
5.2.3790.1653 version 2.0
5.2.3790.1748 version 2.01
5.2.3790.1895 version 2.02
5.2.3790.3099 version 2.03
5.2.3790.3273 version 2.04
5.2.3790.3392 version 2.05
5.2.3790.3497 version 2.06
5.2.3790.3640 version 2.07
5.2.3790.3825 version 2.08

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