How can I get rid of the 'this copy of Windoes is not genuine' error? READ DETAILS?

I checked Youtube videos. At first, running CMD as administrator and typing "SLMGR -REARM" did the trick. But now it only gets me an error that says I've done it too many times. Once I installed updates long before this, it began to show this copy of windows not being genuine thing. I uninstalled the update responsible for it. However, that no longer works either, and I will be able to find it if I check for the Update History (No, I obviously won't be able to delete it there. There's no option nor does the 'delete' button work on it). Note: I have not pirated Windows.