cd key changer problems


I recently downloaded the cd key changer from this sight known as serby d2 cd key but I have no clue as to how it works...
I made a 'new cd key file' with a second key and I'm aware it goes to my d2 folder... and I also tried opening the key with the d2 launcher which worked fine but I was still unable to access bnet due to ' key being used'
I'd like to be able to access multiple accounts on battle net plz help! :(

Ok well I solved my own problem and everythings up and running now... but I'm in need of Diablo II 'CLASSIC' cd key!!!! :(
If anyone could spare me one that isn't in use, I'd appreciate it, thx.