Some manufacturers have a restore facility on the hard disk.
You need to read the manual that came with your PC to
find out if this is the case. If there is no such facility then you
have ro reload Windows using a Windows installation CD.
Where do I get a Windows Installation CD just for that purpose . . . for the
purpose of installing the os onto a pc that no longer have the restore cd
with it, which may also no longer have the license sticker on the side of
it, or any record of the license # that was originally on the pc? Doesn't
Microsoft have a cd just for that purpose? For technicians who are in the
business of refurbishing computers?