Black Edition as in one that someone has "cracked" (for lack of a better word) and added things to it..?
I wouldn't recommend using that.. at least not for an RC release.. If 7 was in the Retail stages then yes it would probably be alright to use.. but an RC isn't a good time to use something like that.. it can and usually does lead to "problems" like the one the OP is having.. That being said, I'm not saying that it won't work, it obviously IS working, I just don't think that's a very good "version" to be using at this point..
![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I'd recommend you download the official release from Microsoft's Website and do a clean install of that..
I have to ask too, why would you prefer to use a Black Edition of an RC? I'm assuming the reason they've dubbed it "Black Edition" is because the time bomb has been removed and or deactivated?
Yet again, I have to laugh to myself because I just don't see the point of cracking a BETA OR RC version of an OS.. Especially seeing as Windows 7 will more then likely be finished and in stores long before the RC or even RTM expires..