Last month, Microsoft released KB3161606, June 2016 update rollup for Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2. This update breaks the upgrade of Hyper-V VM integration services inside the guest. This has been confirmed and reported by several customers.
Some customers have reported that this update is breaking Scale-out File Server clusters as well.
Microsoft was notified and last week they released KB3172614, July 2016 update rollup for Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2. The KB3172614 update rollup override June 2016 update rollup KB3161606 which includes improvements and bug fixes.
At the same time, Microsoft publically acknowledged the issues in the June update under ‘Known issues’ section.
When you deploy July 2016 update rollup to your Hyper-V host, the integration services version is updated one more time from 6.3.9600.18339 to 6.3.9600.18398.
The two scenarios in order to rectify the integration services issue is the following:
1. If your VM had KB3161606 already installed and is failing to update the integration services, you need to follow these steps:
a. You need to install July 2016 update KB3172614 on the Hyper-V host.
b. You need to restart the Hyper-V Virtual Machine Management (VMMS) Service to rebuild vmguest.iso.
c. Last but not least, you need to update the integration services in the VM to the latest version 18398.
2. If you already updated the integration services for your VM before installing KB3161606 inside the guest, then you need to follow these steps:
a. You need to install July 2016 update KB3172614 in the VM.
b. You don’t have to update the integration services for the VM anymore, because the integration services version 18339 and 18398 are identical code wise.
This is was not a pleasant situation for many customers, as a rule of thumb, always deploy and validate the new updates in a demo environment before you move into production.
Hope that helps!