Written for Synergy 3 (v3.7.2) and Synergy 1 (v1.21.4), checked 3 October 2026.
If you're playing a video game or using any full screen app, you may want to lock your cursor to one computer.
Press the scroll lock key on the server's keyboard to toggle the cursor lock on and off. Pressing it locks the cursor to the computer it's on, and pressing it again releases the lock. Most Windows PC keyboards have this key.
If everything was working fine and suddenly you can’t move your cursor from one computer to another, you might have pressed the scroll lock key by accident. Just press the key again to release the cursor lock. If you have set up your own lock cursor hotkey (see below), press that hotkey instead: once a lock cursor hotkey exists, Scroll Lock no longer locks or releases the cursor. If this does not work, you might have a connection or config issue.
If you don't have a scroll lock key (for example Mac keyboards), you can customize the lock cursor key:
Customize the lock cursor key
Your hotkey replaces Scroll Lock: once it's added, Scroll Lock no longer locks or releases the cursor.
Create the hotkey with the steps in: Create hotkeys in Synergy 1 or Synergy 3: switch computers, restart the connection and send keys
For its action, choose:
- In Synergy 3, Lock cursor to the current computer, with Lock behavior left on Toggle.
- In Synergy 1, Modify the cursor lock, with Toggle the cursor lock beside it.
Then check that the cursor lock itself is on. If it's off, the cursor lock is disabled completely, including your hotkey:
- In Synergy 3, on the Keyboard & mouse page, Enable lock to screen (under Advanced) is switched on.
- In Synergy 1, on the Advanced tab of Server Configuration, Disable lock to computer (scroll lock key) is unticked. In Synergy 1.20 and earlier it's called "Disable lock to screen".