First, decide who is going to be your server.
Instructions for Everyone
- Turn off your net connection
- Launch CS 1.6
- Minimize CS 1.6, make sure that the grey hamachi window is open, and Hamachi is powered off.
- Now turn on your net connection and power on Hamachi.
- Now you'll be connected to the network that you had joined previously.
Instruction for Server
- In CS 1.6, Click New Game. Name your server appropriately, and start the game.
- In CS 1.6, Click Find Servers. Open the LAN tab, and click refresh. The server should be the only one on the list. Double click on it to join the game.