If you can't get Synergy to work at all:
If you got Synergy to work, but it's not working properly:
Check out the help article: Known bugs and gotchas
On the Screen layout, multiple computers should show up. If you see only one, then your computers are having problems seeing each other. Take a look at the General checklist at the top of this page.
You can also try manually adding a computer, in case the auto-discovery feature didn't work. Go to Manage computers, and click Manually add computer.
On the Screen layout, click the 3-dots menu, then click Use this keyboard and mouse. This computer's keyboard and mouse will then be shared with the other computers.
Click the Configure Server button on the server computer and add the client computers in to the grid on the Server Configuration screen and place the computers so that the sides are directly connected along the edge of another computer.
You only need to add a client computer once, even if you have multiple monitors, because Synergy will treat all screens on one computer as "one big screen".
In the Server Configuration screen, double-click on each computer to change the Screen name. This needs to match the client name that you gave.
The names entered should not contain spaces (neither in the middle, beginning, the end of the name). Please also check that you are only using UTF-8 characters (see below).
After making any change on the server or the client, always click Apply. This will restart the core process and apply any changes to settings that you've made.
If this article didn't help, you can talk to someone on our support team (unless we sent you here, in which case please reply via the ticket you already have open).