HelpCracked Servers

Hey I realised that there are some servers that are no cdkey but when I try to join one it says "Bad serial number given in setup" and I have tried using a banned key and it says that it is globally banned.

Any ideas?

Filter for no CD Key and Battleye Disabled. There are a few out there

you have to use an invalid cd-key (i think, i just always used them key generators that always generate invalid keys)
or no battleye at all on the server

As long as battle eye is off then you can play on it with a banned key, I normally play on them to hack because i cant afford a bypass ;(