NOTE: Cursor is locked to screen, check Scroll Lock key
NOTE: Cursor is locked to screen, check Scroll Lock key
NOTE: Cursor is locked to screen, check Scroll Lock key
NOTE: Cursor is locked to screen, check Scroll Lock key
NOTE: Cursor is locked to screen, check Scroll Lock key
NOTE: Cursor is locked to screen, check Scroll Lock key
NOTE: Cursor is locked to screen, check Scroll Lock key
NOTE: Cursor is locked to screen, check Scroll Lock key
Same for me.
I was same.
It's a dupe of #4009
Press "Scroll Lock" button to let the cursor go to a Client's screen.
That's the key my cats keep pressing!
Not realizing that this is actually a feature, I encountered the locked mouse+screen and had no idea what to do. At least on Windows 10 it would be nice to get an alert from the "Action Screen" that the mouse has been locked to a screen. The fact that this happens without any notice is actually disturbing considering the repercussions if you don't know what's happened. BTW, I'm on "1.8.1-beta-f7377d6".
bytebuster463's answer works, thanks.
I don't (being on a laptop) HAVE a Scroll-lock key, either on the Mac or the Dell.
Can this alleged feature be disabled?
Opening the on-screen keyboard will I'm sure become rapidly tiresome.
If anyone whose keyboard does not have the Scroll Lock key (like mine), or it fails to work, just reboot (stop and start) the synergy server, and the client will connect to the server (automatically) again.
Stop and start synergy server didn't solve for me. Opening 芦on screen keyboard禄 first and unlock cursor by turning Scroll Lock Key off just did it. Hope it helps!

@nbolton Is there a reason you marked this issue as closed, as well as the apparent dupe #4009... was there another issue we're not aware of where this was solved? I'm using 1.10.3_stable and I'm not receiving any notifications when locking screens, and the log still doesn't indicate that "scroll lock" is the culprit when cursor locked to current screen. What's up?
Most helpful comment
It's a dupe of #4009
Press "Scroll Lock" button to let the cursor go to a Client's screen.