Dan said:
How would I use a single installation operating system that has been
installed on an old computer, on a new one? Do I have to release the
registration before using the operating system on a new computer?
Was the OS installed on the old computer by you or did the old computer come
with the OS installed (and possibly a sticker on the computer with the COA?)
If you bought and installed the OS yourself, did the OS come in a nice box
or wrapped in cellophane with a cardboard backing (possibly)?
Does the installation media for the old OS have "OEM" on it anywhere?
If pre-installed, if cellophane wrapped or if it does have OEM on it - then
you cannot (by the terms of the EULA) transfer the installation in any form
from the original install - no matter what happens to the machine.
If it is a RETAIL copy - meaning you bought it at a store, nice box, etc -
then format the old machine - install on the new machine - activate - move
on.