So, as many IT admins have found out, Microsoft released KB950049 the other day. (Taylor Brown's announcement) This patch updates Hyper-V from RC0 to RC1. But it dosn't work. On 100% of my servers, applying the patch to the guest OS left the guest without a network card and when logging into the console via Hyper-V, there was no mouse integration. Applying the patch to the host OS seemed to work ok.

Let's say first that I'm not the only one to have issues with this update.

This post on John Howard's blog pointed me to the VMBus device. Sure enough, it was in a "having problems" state. Then I went back to Taylor Brown's announcement and noticed the line that says that there are new Integration Components and that they are part of the disk image. Nice! So I'll just reinstall the integration components! ... NOT!! The integration components don't show up in Programs and Features control panel or in the Installed Updates, and you can't reinstall them. The setup just says that it's already installed, and goes away.

So I went surfing through the integration components disk and I found that the disk is basically a bunch of drivers and an installer wrapper. So here is the process that I finally managed to use to restore all of my virtual servers.

1. Remote into your host system. Logging into the console is better so that you can use your windows keys, but remote desktop will work too.
2. Connect and log into your busted guest OS.
3. Use the Action > Install Integration Components menu item to attach the IC disk.
4. If server manager comes up, then good. If not, figure out how to launch it using only the keyboard. :(
5. Navigate to Diagnostics > Device Manager
6. Find the VMBus device (under System devices) and use the windows context-menu-key (right click) to start the "Update Driver Software..." process. Or press enter, and navigate to the Driver page and the "Update Driver..." button.
7. Choose "Browse my computer"
8. Enter the path "CD_DRIVE:\support\x86\", Include subfolders, and press Enter until the driver is updated.
9. Reboot the guest.
10. YOUR MOUSE SHOULD NOW WORK IN THE GUEST OS.
11. Do the same thing for these devices without rebooting:
    
    • Display Adapters > Microsoft VMBus Video Device
    • Human Interface Devices > Microsoft HID
    • Network Adapters > Microsoft VMBus Network Adapter (it's probably yellow right now)
    • System Devices > Direct Virtual Machine Bus Acceleration Filter Driver (both of them)
    • System Devices > Hyper-V Data Exchange
    • System Devices > Hyper-V Guest Shutdown
    • System Devices > Hyper-V Heartbeat
    • System Devices > Hyper-V Time Syncronization
    • System Devices > Hyper-V Volume Shadow Copy
12. Reboot and enjoy your working Hyper-V Server.

Really, someone at Microsoft needs to take notes. If you're going to publish an update that can't be remove, please at least provide a means to Reinstall or Repair the installation.

Labels: Hyper-V, KB950049, Microsoft, Windows Server 2008