Determining versions under Hyper-V

Every now and then we need to determine the release level of a component that we are running.

In the case of Hyper-V, if you have the role installed you can check the version of vmms.exe

There is the GUI way:
Browse to \windows\systm32\vmms.exe and check the properties -> details tab

There is the command line way:
wmic datafile where name="c:\\windows\\system32\\vmms.exe" get version

you should see a build version either way - here is the breakdown:
Beta Version of Hyper-V installed == 6.0.6001.17101
RC0 version of Hyper-V installed == 6.0.6001.18004

Now, you don't have the Hyper-V role installed and you want to check the release level of the Integration Components. (this also works within a VM to check the version installed within a VM)
We just look at different files.

Open Device Manager and find one of the vmBus devices (vmBus Network Adapter, VMBus HID Miniport, vmBus Video Device), open its properties, on the driver tab, check the driver version.

The version will end in 18000 if you are running Beta Integration Components
The version will end in 18004 if you are running the RC0 Integration Components
...
The version will end in 18016 if you are running the RTM Integration Components

If you need to update Hyper-V or its integration components under Windows Server 2008 then install patch KB949219 to move to the RC0 release. To update any other supported guests insert the Intgration Services Setup Disk from the Connect client window and let autorun do its work (assuming a Windows guest).