Before opening Hamachi for the first time: (If you already opened it, install and uninstall it again)
1. Right Click on Network icon.
2. Open the "Network and Sharing center resources".
3. Click on "Change adapter settings".
4. Press Alt key to show hidden menu and click Advanced -> Advanced Settings.
5. Select Hamachi from list and press upper arrow until Hamachi is on top. Then select TCP/IPv4 for Hamachi list.
7. Right click in Hamachi and Select Properties -> Advanced. Uncheck Automatic metric and set Interface metric to 1.
Main source (pictures included):
http://wiretuts.com/how-to-get-games-to-work-with-hamachi-on-windows-8/