Registry Editing has Been disabled by your administrator

1- From Group Policy Editor

Go to Run –> gpedit.msc
In the left hand menu, go to User Config –> Administrative Templated –> System.
Now In the right hand pane, select “Prevent access to registry editing tools”. It will probably be not configured or enabled. If it’s enabled, disable it and if it’s not configured, first enable it, apply settings and then disable it. Most probably the settings have been applied instantly. If not, then run gpupdate in command prompt to apply the group policies.

2- From the Run Menu

I got this tweak while surfing the internet. Go to Start –> Run, copy and paste the follow in the Run box and press OK.

REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableRegistryTools /t REG_DWORD /d 0 /f

The effects are usually instant. If not then you should see the results after restarting your computer.