So whenever I've tried to activate (back when the KMS servers were online), I would get an error saying I was using a non-core edition or something and to look at SLUI.exe. So if I type slui in 'run', then I get "There are files on your PC preventing activation" and it tells me to restart. I've restarted heaps of times and nothing has changed. How do I fix it? I'm running it on 64-bit Enterprise RTM (non-n).
Check out Windows 8 KMS activation thread around Aug 13. There's a bunch of posts on the subject. I had the same prob myself, can't remember how I fixed it, but I got the clue from this thread.