When is a Cumulative Update not a Cumulative Update? When it's a security patch. #BadJoke #Lync2013 #SfB2015

Updated 22:21 BST, Skype for Business is now re-released as a full Cumulative Update - did this post help :-)

Updated 6th October - new FULL CU out for Lync 2013 that includes the security patch

Quick heads up that the September 2015 security update for Lync Server 2013 and Skype for Business Server 2015 is delivered as a CU installer *BUT* without previous updates included:

"Before installing any updates for Skype for Business Server 2015 or Microsoft Lync Server 2013, the latest publicly released Cumulative Updates for Skype for Business Server or Lync Server must be installed"

This does lead to an issue that has been seen already where CU's are getting out of step and indeed is called out in this update:

"Known issues:
After you install this security update on a system that is running Microsoft Lync Server 2013, you find that the Central Logging Service is not listening on designated ports.
Cause
This problem can occur if you install this security update on Lync Server 2013 before you install the August Update of Lync Server 2013.
Resolution

If you already installed this security update without first installing August 2014 Update 5.0.8308.738, you must uninstall this security update, install August 2014 Update 5.0.8308.738, and then reinstall this security update."

(Unsupported fix: http://aspoc.net/archives/2014/09/30/error-lync-server-centralized-logging-service-could-not-be-started/)

So taking a brand new RTM install of Lync 2013 to get fully up to date you would need to:
  1. Install August 2014 Update 5.0.8308.738 OCSCore.msp (although that appears to have issues too!)
  2. Patch to July 2015 cumulative update 5.0.8308.920
  3. Patch to September 2015 Security update 5.0.8308.927
For Skype for Business Server 2015 the process is a little easier since there is just the one CU out at the moment:
  1. Patch to June 2015 cumulative update (6.0.9319.55)
  2. Patch to September 2015 Security update (6.0.9319.72) Updated as 10 hours later Microsoft revised their security update.
I would hope that the next *real* CU for both products Lync 2013 actually become true CUMULATIVE updates and include all previous versions with no requirement to uninstall/reinstall individual components..... but I'm not holding my breath!