I have a Minecraft Bukkit server running on our Hamachi group IP. One of my friends can join, without timing out. However when my other friend joins everything stops moving, and he times out.
It has started happening since he upgraded from Windows 7 to 10. Occasionally he can stay on the server, depending on the map and time, however this is very rare. He can connect to other Minecraft servers and can also connect to our Hamachi servers on any other game.