With this tutorial, you can play Counter Strike 1.6 online.
Step 1: Install cs16full_v23b_2_5 and everything else it offers
Step 2: Install update (csupd1dz.exe)
Step 3: Install CS16_Patch (from third file)
Step 4: Replace C:/Program Files/Counter-Strike 1.6/platform/config/ServerBrowser.vdf with the provided file(from third file).
Step 4.1: Or you can use the provided serverbrowser.exe (cracked) to install a ServerBrowser.vdf to C:Program FilesCounter-Strike 1.6platformconfig if the provided is not working for you.
Step 5: Open Start > Programs > Counter-Strike 1.6 > Counter Strike 1.6 No Steam
Step 6: Click 'Find Servers' and select a server.
Step 7: Play!