Upgrade Windows 7 Professional to Windows 7 Ultimate

We need to update our server from Windows 7 Professional to Windows 7 Ultimate in order to use BitLocker. The only upgrade we could purchase was the Windows 7 Ultimate Anytime Upgrade. We cannot get the key to work. Is this because the upgrade is intended to go from Home Premium? Is there a more appropriate upgrade sku for our situation?

I know it sounds straight forward, but did you try to contact Microsoft, the behavior you describe seems very strange.

Call M$ support and tell them your situation. They help you through it. They are for the reasons you've stated. Don't worry they won't give you the 3rd degree.

Let me know what MS Support says. I may find myself in a similar situation. I ordered a new system and it comes with Win7 Home Premium 64-bit. As I already have several MSDN licenses available for the full version of Win7 Pro and Ultimate, I was reluctant to pay the $150 extra to step up to Win7 Ultimate.

I'm wondering if I can use my existing license for Win7 Ultimate to do a Windows Anytime Upgrade (in-place upgrade) of Win7 Home Premium to Win7 Ultimate. As I understand it, a Windows Anytime Upgrade is more like a configuration change rather than an install. I would rather not go through the hassles of an install on a new system.

Thanks in advance...