Windows 7: uninstall win7 ultimate

will windows registration server automatically detect if I uninstall Windows 7 on one machine and reinstall on another (ie, will it accept the license key on the new machine, or will I have to jump through hoops?)

You may need to phone MS, when you reinstall.

Activate Windows 7 by Phone

If you have activated Windows on one machine and want to move it to another machine and activate it you'll have to call M$. Here's a guide: Activate Windows 7 by Phone

thanks...now if you could help with media center on my homemade machine - I can't get a picture in live tv with 2 hauppage tuners installed and hdhomerun dual tuner box. Wintv7 works, hdhomerun doesn't show a picture or sound, mcenter has sound but no picture. 2 clean installs of Windows 7 home premium later, and still no go. gpu is ati radeon 4650, I've updated, uninstalled, re-installed just about everything, but no pic.

That's a new question for the Media Centre thread. Sorry, I can't help with this one

Re you original question: My experience has been that sometimes MS will complain, but always after calling them and explaining the situation then all is in order. I have MS to be very flexible in this area. I would even say that MS has been customer-friendly in this regard.

The deactivation of old activation is done when you trade numbers during the robocall, as is the new activation.

It basically updates the hardware signature stored for that Product key..