If like me you are a little fed up of going through the process of turning of Windows firewall > restarting Synergy service > starting Synergy > connecting > turning back on firewall then you may wish to use a batch file to make the process easier...
I am no expert and there may be a better way of doing this but this is what I have used and it works for me. Copy the following commands into Notepad and save on your Desktop with a suitable name like 'restart_Synergy.cmd' on the computers you want to connect. When you want to connect right click the file and run as Administrator. You may wish to adjust the timeouts a little so that they are running at roughly the same time giving yourself enough time to jump from one machine to the next:
taskkill /F /im synergy2.exe
NetSh Advfirewall set allprofiles state off
net stop Synergy
net start Synergy
START C:\"Program Files"\Synergy\synergy2.exe
NetSh Advfirewall set allprofiles state on
If you have any issues, Google CMD batch files. I hope this is helpful to other people.