Synergy on Mavericks (OSX 10.9) and enable assistive devices
Solution 1:
From a terminal:
sudo open /Applications/Synergy.app/Contents/MacOS/Synergy
Then open OSX System Preferences and click Security & Privacy, then click on Privacy and then Accessibility
Check the checkbox on for Terminal and Synergy.
You can then close Synergy and start it again in the background through the terminal:
/Applications/Synergy.app/Contents/MacOS/Synergy &
I expect this will be fixed in the next release (1.4.16 Beta)
Source: http://synergy-foss.org/osqa/questions/1999/error-1410-on-mac-1081
Solution 2:
If it's still not working after rebooting, it seems that Mavericks needs the settings to be "reset" if you've already had this setup before. To get it working again, I had to untick Terminal / Synergy.app, lock, unlock, re-tick Terminal/Synergy.app, lock, then it worked. Now Synergy starts normally without needing the terminal anymore.
Solution 3:
The just-released 1.4.16 Beta version for OS X 10.9 now resolves this issue and allows Synergy to be opened directly rather than requiring sudo.
Note: After installing Synergy-1.4.16 and opening it the first time I had to reboot to get the appropriate Accessibility preference to become available.