virtualbox.org

Hello all,
When I clone a Windows guest hd, I usually change the UUID of image so I can run multiple copies of same installation. However, In the case of Win7 the new installation detects the change in UUID and asks for re-activation.
Is there a way around this problem?

(One thing I can do (have done) is to run the cloned hd (without changing uuid) under a different user account in Windows or Linux or an entirely different computer. It's possible because VirtualBox.xml is different for each user - so VirtualBox won't complain about identical UUIDs.)

Windows activation generates a hardware hash, giving a number of votes to different parts of the hardware.

The most important thing in the hardware hash (with the most votes) is the type of the first network adapter (Vendor / Device ID) and the MAC address. If you make sure to use exactly the same network adapter and MAC address for the first network adapter then you can usually avoid having to re-activate Windows.

The disk serial number and other information such as memory size goes into the rest of the hardware hash. If you don't change anything else but the network adapter type or MAC address then you can usually avoid re-activating Windows.

When you change the network adapter information and some of the other information (disk serial number) then you usually do have to re-activate Windows.

If you search for Windows Activation you will find a number of white papers describing how the hardware hash is generated. Those are not considered activation hack information because they don't tell you how to defeat the activation. They only describe what information is used and how the voting is done.

Of course, some people have created ways to bypass Windows Activation. Bypassing Windows Activation is not illegal. Running an un-licensed copy of Windows is illegal, whether activation complains about that or not. Bypassing Windows Activation doesn't make a copy of Windows "legal". Strictly interpreting the Windows End User License Agreement, one should buy a license for each copy of Windows running in each virtual machine.

So the most important thing to avoid activation problems is to keep the first network adapter exactly the same, including the MAC address for the adapter. To avoid legal problems, purchase a license for each copy of Windows running in each virtual machine. The Windows Activation and the license are two totally separate things.

You may also wish to review the discussion in the "Which changes trigger reactivation in a Windows guest?" sticky at the top of this forum. Tip: a change in VM UUID (not the same as the disk UUID) can contribute to Win7 reactivation. Whether keeping the MAC address the same prevents it, I don't know: I've never installed a Win7 guest.