I have QuickCursor in my Login Items and after upgrading to OS X Mavericks I saw the following message pop-up.
I’ve seen this message before, shortly after installing QuickCursor the first time. So I opened up System Preferences and clicked on the Accessibility Pane where I expected to find the option to enable assistive devices. Unfortunately, the old check box for assistive devices was gone. Looking at the options available and none seemed to apply.
I poked around in the options trying to find something that would work. I started to get frustrated so I open a browser. After a few minutes of searching2 I found the answer.
Apple has changed some of the security preferences of Mavericks to more closely match those of iOS. The option to enable accessibility for apps had move to System Preferences->Security & Privacy->Privacy-> Accessibility. This allows the user to choose which apps can gain access to these features. Once I unlocked the preference pane I selected the check box for QuickCursor to enable access to assistive devices.