Give me back admin rights on Win7

Question

I (current user) was a member of Administrators group. I changed my group to another one. Now, I can't change back to Administrators:

Also, this command (and several others) was denied:

net user administrator /active:no

How to become a member of Administrators group again?

Solution

You need to re-join the Administrators group through the Windows' built-in (but almost always hidden) Administrator account. The command you're trying to execute (net user administrator /active:no) actually disables the built-in Administrator account and I'm not sure why you would execute this... Because that would leave the computer with no accessible account that has Administrator rights, access is denied.

Log in using the Windows' built-in Administrator account (if not visible in the login screen, use this on an elevated command prompt: net user administrator /active:yes) and re-add your user to the Administrators group. You can then disable the built-in Administrator account using the command.

Comments

[edusysadmin]

Did you make sure to run the net user command from an elevated CMD prompt?

[mmdemirbas]

Yes, I think so. Right click cmd.exe and "Run as admin" does the work?

[mmdemirbas]

Unfortunately, net user administrator /active:yes also denied

[mmdemirbas]

And I don't now Administrator password :(

[mmdemirbas]

My system admin logged on as Administrator and added me to Administrators group. Problem solved. Thanks @BloodPhilia :)