You can do a clean install of any Windows version you have a license key for. There might be one for Windows 7 or 8 on a sticker. Or use Belarc Advisor or Jelly Bean Keyfinder (both free) to find it.\
Use Microsofts Media Creation Tool to make an install disc. Use the Lenovo site to get all drivers.
Purchased Lenovo E93z ThinkCentre using Windows 8 Pro (which may or may not have been downgraded to 7) from hotel that was closing. Very limited access to any programs. Cannot access Settings, Device Manager, Computer Management, Internet, etc. Was told I would need to do a re-installation of operating system to clear all of the blocks in place. Tried using the Lenovo built-in recovery partition but seem to not be present.
Can I do a factory restore using Windows 10 or some other method to get it to work. There are no files on the computer that I want to keep. Thanks

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