Warden is Blizzard’s anti-cheating technology. Essentially bnet sends periodic ‘challenges’ which must be answered correctly by the client program in order to stay connected. In my opinion Warden is intended to stop cheating, not bots (they are just collateral damage).

Tinker is unable to answer Warden challenges on its own. It must forward the challenges to a BNLS (battle net logon server) server, which tells Tinker the proper response. You must tell Tinker which BNLS server to use by entering the server’s location into Tinker’s settings. You can find BNLS servers by googling “BNLS server”.

If you do not enter a server, and Warden is running (sometimes Blizzard has Warden off) Tinker will be disconnected soon after connecting to bnet. Note that Tinker only uses uses BNLS for Warden, not for the actual logon process. Your cd keys, username and password are not sent to the BNLS server.