How do you take a hard drive out of a computer and make it work in another computer

If your OS is OEM, these steps may not work. Consult your computer manufacuter for better advice. Depending on the hardware, the OS, etc, generally speaking, to take a HD out of an old computer, and make it work in a new computer, you will have to force the Hardware Abstraction Layer to re-run. The HAL is responsible to querry the actual hardware and attempt to install the approriate drivers for that hardware. To do this, install the old HD into the new hardware. Now, before trying to boot the machine, put a copy of the Windows Cd into the CD-ROM drive, and boot from it. At the first menu, select "Install Operating System" Affter this, you will see the Microsoft EULA. Press F8 to accept. This next step is important. After accepting the EULA, MS installation should see that you have a previous OS installed, and offer to repair that installation. If this is the case, you can select Repair, which re-invokes the HAL, and will reinstall your motherboard drivers. If MS installation DOES NOT FIND AN OS TO REPAIR, stop, unplug the computer and get professional help. Failure to do so will result in lost data, and perhaps a non-functioning computer. If it does find your previous OS, go ahead and select repair. AFter completion, you may still want to check with the manufaturer website and update the hardware drivers, but generally speaking, this will get you back to a working OS.