Device installation forbidden by system policy

Is your PC, or has your PC ever been on a domain at all, e.g. added to a server domain like in a workplace etc?

If not, try going to Start > Run, type in gpedit.msc and press OK. Go to Computer Configuration > Administrative templates > System > Device Installation > Device Installation Restrictions.

In here are loads of different settings which apply to installation of new devices, make sure they are all set to "not configured" apart from the very first one which says "Allow administrators to override restrictions" etc.

Another thing: Go to Start > Run, type in rsop.msc and post on here what policies are being applied.

Also post the result of this: Go to Start > Run, type in cmd, into cmd type SET, press enter and post whatever USERDOMAIN= is.

In my case the group policy was not configured, while the resultant policy device install restriction was enabled, didn't find anywhere to remove this restriction, then i found this registry key HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\DeviceInstall\Restrictions Removing keys with restrictions from there solved my problem http://amir-shenodua.blogspot.ie/2017/01/setup-blocked-by-group-policy.html