User [domain\user] is not authorized to start [Real-Time Monitor\Schedule]

When you receive a User [domain\user] is not authorized to start [Real-Time Monitor\Schedule] message, it indicates the user account in question does not have permission to launch Jobs in the relevant Group Folder Security. 

To correct the issue, launch the SureSync Desktop. Click on the relevant Group Folder and click on the Security tab. Correct the permissions and click "Apply."

Keep in mind that Group Folder Security operates like NTFS permissions. By default, all Jobs/Schedules and Real-Time Monitors under a Group Folder inherit security from the Group Folder. It is possible to turn that inheritance off on the Security tab. If you have done so in your environment, the permissions may need to be corrected on the Job, Real-Time Monitor or Schedule itself.