Last month I wrote about how it’s possible to upgrade a retail copy of Windows Vista to an Enterprise version and it turns out that this is also possible with other versions of Windows.

Last week I needed to build a new server with Windows Server 2003 R2 and my colleague who was supplying the media only brought 32-bit CDs with him (with 8GB of RAM for this server to run multiple virtual machines, it makes sense to use a 64-bit operating system). I spent most of the day downloading 64-bit CD images from various file shares around the company (in theory, because we’d bought the appropriate licenses, it shouldn’t matter what media we used) but when the volume licensing key (VLK) that I’d been given didn’t work we realised that the disc image we were using was an MSDN version. After supplying a product key that did work and going through all the hassle of getting the server added to the corporate domain, Windows notified me that I had 55 days left to activate the product, so I finished installing the applications today and then “upgraded” using the correct volume license media and key, removing the requirement for product activation.

Another point that’s worth noting (thanks to Daniel Petri for this tip) is that the .IMG files that Microsoft provided in the “ISO only” download appear to be just ISO 9660 (.ISO) files with a different file extension. Either way, the cdburn.exe resource kit tool was able to write them on my Windows Vista PC (although it did report an error when trying to eject the CD).