If you want you can paste the results of
netsh interface ipv4 show subinterfaces and
so I can have a look and see if theres anything glaringly obvious..
>> Yes, I am running cmd as Administrator
but I will be honest and say it should work then and I cant think of any reason why its throwing up that particular error
Ive tried googling it, but its so vague that it can apply to lots of things - but normally if it cant find the device you are trying to amend. :/