I just found this by chance and I haven’t checked on the net for an explanation to this. 
I have a VM with Windows 7 operating system. The VM image was created using VMWare Workstation and it is already working in my host machine with a licensed serial key. I have to move the image from my laptop to another machine that will host the image. So, I copied the image files to the new machine and opened the VM there. On first load of the VM, you will be shown a dialog box saying “The virtual machine may have been moved or copied.”
I have been ignoring this for the longest time ever since I started using VMWare. I have been wondering the sense behind this until I ran into activation errors in Windows 7.
When I selected the “I copied it” option and clicked OK, the VM loaded but Windows 7 complained that it must be activated and you’ll see a note at the bottom right portion of the desktop saying that the OS is not genuine.
I copied the VM files again from my original source and overwrite the one in the new host machine. I did this because the dialog box did not show up when I shutdown and reloaded the VM again. When I selected the “I moved it”, the VM and Windows 7 loaded well with no complaints on the activation.
Have you encountered the same problem before? Do you know of an explanation to this?
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Great! I’ve always wondered what’s the difference in these 2 options 🙂 thanks!
PS: sorry for off-top, but I’m as .NET developer interesting in developing for iPhone – is it comfortable, easy to learn for .NET guy or this is really another universe?
Developing for the iPhone is indeed a whole new world! 🙂 You have to familiarize yourself with a lot of things: Mac OS, even the Mac machine keyboard layout, Objective-C, IDE (XCode, Interface Builder, etc.), look and feel of iDevices (iPhone, iPad, iPod Touch), etc. The good news is at the end of the day, if you really want to learn it and commit your time to understand it, you’re going to overcome these challenges. It won’t be easy at first but your knowledge of .NET plus books/tutorials on iPhone development and http://www.StackOverflow.com forum will help you go through it.
Huh, I’m having the same problem and generally to avoid problems you’re supposed to always take “I copied it” the default. I’ll try again with the I moved it option which seems counter-intuitive as that’s supposed to be the option that changes the MAC address which triggers WGA activation. Weird. If this works then you have my gratitude for posting.
Wrong, it changes the MAC and stuff when you say the machine is copied… this is because it assumes there is another VM with the same MAC address running.
Yup, that did the trick, very strange, I guess what I thought I knew about that option is all wrong. Thanks for the post.
This is an unputdownable article, I agree with most of the points. thanks for this intimation !
What you are really selecting when you choose this is wether or not VmWare should generate a new MAC address for the network card and maybe a few other things like that. The MAC address is how network gear communicate (below the TPC/IP layer). What happens is that when you say “I copied it” VmWare will assume that it is on the same machine/network. Therefor it needs a new MAC address for the network card so there will be no collisions on the network. When the guest OS sees that it assumes this is a new machine. When you say “I moved it” VmWare assumes that it is on a different machine/network and will leave the MAC address and those other settings alone.
Nice explanation ray! Thanks! 🙂
More to ray’s explanation – It also changed the UUID of the machine if you select I copied it., but unchanged when you select I moved it.
Great Info.
I wanted to get rid of an old loud behemoth of a an HP XP Media Center PC I have laying around. My idea was to create a VM and keep that on my new physical machine in case I realize later that I need data or to run a rarely used application.
I am willing to cough up more money to MS to do this if my original cheaper OEM licensed copy does not allow me to transfer the OS to a new VM but I do not want to pay for a new license every time I move the VM to a new host physical computer. At that point I would just leave the old physical machine in storage.
This is a great solution for me. I am still going to wait to activate until I move the VM to the new physical computer because I currently have the VM set up to only use a single core CPU & 128MB of RAM & I will probably give it a dual core CPU & 2GB of RAM on the new physical computer. I don’t want a change in the number of CPU cores to trigger another Windows Activation request.
Thanks again for the great info.
Microsoft checks the UUIDs (or a special hash of some UUIDs) of some hardware devices. When one or more of these UUIDs change after Windows has been activated, Microsoft wants to confirm that you aren’t using the Windows OS in another machine.
Why is this important?
When you select the “I copied it” option, VMware generates new UUIDs for the copied VM’s hardware so that it does not conflict with existing VMs you may have.
When you click “I moved it” VMware assumes that VM is not a clone of another VM, so it doesn’t modify the UUIDs since there will be no UUID conflicts.