You can enable the built-in Administrator account by opening the Start menu, type 'lusrmgr.msc' in the search box, then press Enter. If prompted by UAC, click on Yes. In the lusrmgr console left pane; click Users then double-click Administrator which will open the Administrator Properties dialog.
Uncheck "Account is disabled', click Apply, then OK to close the dialog. Highlight Administrator then in the right pane click "More Actions" and select 'Set Password' from the context menu which will open the 'Set Password for Administrator' dialog. Read the warning, click "Proceed", type and confirm the new password, then click OK to close the dialog. Close the lusrmgr console and reboot. When Windows boots to the login screen you'll now see the Administrator icon in addition to User icons.
Login to the Admninistrator account and again open the lusrmgr.msc. Using the previous procedure; simply null the Users passwords by setting them blank. As always; backup before making changes.
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