reinstall old windows

[jacobidaddio]

how do I reinstall old windows

 

[Phillip Corcoran]

You mean the version that was pre-installed at the factory before you upgraded?
If yes, that depends on whether or not the Recovery Partition on the hard drive is still intact.

Look in Control Panel > Administrative Tools > Computer Management > Disk Management

if you see the Recovery Partition there, please post make and model of your laptop or desktop PC as the recovery process varies by make and model.