Hello to all: I'm having a problem activating Windows 7 on an HP machine and I could use expert advice right about now. I performed an upgrade of Windows 7 from Windows Vista Ultimate (not a clean install) so that I didn't have to spend hours reinstalling all my programs again. Because I hit upgrade, setup of course did not ask me for the edition to installed--it just installed 7 Ultimate. After installing the HP-Compaq xrm-ms license, 7 will not accept any of the four Ultimate keys (from other OEM's). According to many threads the key doesn't need to correspond to the OEM vendor, just the certificate. It doesn't work, though. I know the computer supports SLIC 2.1 because the original system that came with this machine is Windows Vista Ultiimate. I suppose I can wait 120 days by rearming until someone finds an HP Ultimate key, but has anyone had this similar situation and knows what I'm doing wrong? If so, is there a workaround? Any assistance would be appreciated. Thank you in advance.