Open up your cmd as Admin..
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Now type in
C:/>net user administrator /active:yes
"yes" --- to Activate
"no"----to Disable
log off from current user, You can see the Administrator Unleashed!
Now type in
C:/>net user administrator /active:yes
"yes" --- to Activate
"no"----to Disable
log off from current user, You can see the Administrator Unleashed!