My Experience: I needed to move my old OS (Windows Vista) to the new computer I was building. Unfortunately, I had only bought upgrade versions of Windows 7. I needed to move the hard drive from my old system to the new system while keeping the OS intact so an upgrade could be done. I would not normally recommend moving an OS from one machine to another in this way, but I will do a clean install of Windows 7 right after I get the new machine running.
The Cause: Computers are not magic after all. The bunch of new hardware will not mesh with the configured OS automatically.
The Fix: These are possible fixes given online and their sources:
((1)) Connect old HD to new PC
Boot from your XP CD
Do a repair install
(http://www.windowsbbs.com/windows-xp/32188-move-operating-system-another-computer.html)
((2)) Before you shut down the old computer to remove the harddrive, go into Device Manager and delete everything there...yes, everything. Then shut down, take the drive out, put it (and anything else you want) into the new computer and boot up. Keep your fingers crossed that XP will recognize the new motherboard and adjust accordingly.
(http://www.windowsbbs.com/windows-xp/32188-move-operating-system-another-computer.html)
((3)) I used to do this professionally. Here is my recommendation:
1) Boot the hard drive in the new computer in Safe Mode.
2) Go into Device Manager and remove EVERY device in the list since they are all devices and drivers from your old system.
3) Reboot normally. You will have to install drivers for every component in the new system, same as a system format.
(http://ask.metafilter.com/94202/Move-HDD-with-OS-to-a-new-computer)
((4)) I had to do this a couple dozen times at a previous job. Here's what I did:
1 - Download all the drivers you'll need for your new motherboard to the hard drive. Don't try to install them yet, just download and save them.
2 - Install the hard drive into the new computer.
3 - Boot up from your Windows 2000 CD - NOT the hard drive - and do a Repair install.
4 - When the Windows CD is done and your computer boots from the hard drive, install any missing drivers. This will be easy since you had the foresight to save them to your hard drive before you began. :)
(http://ask.metafilter.com/94202/Move-HDD-with-OS-to-a-new-computer)
((5)) There is a small chance I can do this in my case. You CAN move Windows operating systems from one computer to another if you have a non-OEM key and have the original installation cd. Unfortunately, all versions of windows I have had are OEM since they were from Dell or the vista upgrade I got after purchasing my last computer.
To do this, all you need to do is:
1. (optionally) Remove the OS from the old system by uninstall.
2. Install the OS on the new system.
3. Try to enter the product key online, if it fails, try to use the phone activation option.
4. If entering the product key to the automated phone program fails, then wait until you are connected to a real person.
((6)) If you're legally allowed to upgrade to Windows 7, you can do the double install trick. Install from your upgrade cd WITHOUT endtering a product key, then run install again and enter a product key.
My Results: Yet to be seen.
