imageOne of the questions customers often ask is what the heck does the new /vm switch do in Sysprep.exe. Well here is the secret…

What the /mode:vm switch does
Running SYSPREP removes unique information, such as the SID and GUID, but it also resets the hardware drivers information. When you run Sysprep with the /mode:vm switch you don’t remove the hardware information. This means the machine doesn’t need to redetect hardware on it’s first boot enabling a faster process when creating new VMs.

Command Line Only
VM mode is available only through the command line. It is also supported only when you run it from inside a virtual machine and deploying to a virtual machine of the same type. (i.e. Hyper-v Gen1 to Hyper-v Gen1 or Hyper-v Gen2 to Hyper-v Gen2)

Here is a side note…
I spent a good half hour a few years ago looking for the Sysprep.exe download on the internet. Guess what? You won’t find a sysprep download as it is already in all Windows installs. Ouch – it still kinda stings…

To Run Sysprep
Open a Command Prompt window as an administrator. Change to the C:\windows\system32\sysprep directory. Type:

Command Description
Sysprep /generalize /shutdown /oobe Standard command for real hardware
Sysprep /generalize /shutdown /oobe /mode:vm Command for a Virtual Machine


For more info on Sysprep see the Technet article here: