Have you tried to run the command in elevated command prompt?
However, you may first try to enable the default administrator on your computer and later try to run the command in elevated command prompt and verify if your are able to run the command successfully.
To enable the default Administrator account, perform the steps below:
1. Click Start and type CMD in the Start search box
2. Right click on CMD in the list and click on "Run as administrator"
3. Type the following command: net user administrator /active:yes
Restart the computer and you should see an "Administrator" account.
Access Administrator account and follow the steps 1 and 2 and try to run the command.