Uninstalling Virtual Machine Additions on a Windows 2003 Server Moved from Virtual Server to Hyper-V
Posted by Russell Wright on December 16, 2010
If you are moving a VM from Virtual Server to Hyper-V and can’t uninstall the VS additions (which is a requirement before being able to install integration services), here is a little hack I found reading http://social.technet.microsoft.com/Forums/en-US/winserverhyperv/thread/d803c97a-5d4e-4643-8ea6-1ff51184b133/.
I added some updates to show the items that were removed from the MSI file, using the Orca MSI editor (http://www.technipages.com/download-orca-msi-editor.html).
The two actions that need to be removed from the MSI file are CA_CheckForRunningInsideAVirtualMachine and Error_CheckForRunningInsideAVirtualMachine. Simply select each one and press the delete key and save the MSI file you may want to back up the MSI file before you do this).
Then you should be able to remove the Virtual Machine Additions without a problem.