The following script when run on your SQL Server instance will show all schedules that are disabled but more importantly will show those schedules that have jobs associated with them. This is important because it will help identify those jobs that may not run because the schedule has been disabled. The last thing any concerned DBA will want is a job that has been scheduled but will not run because the underlying schedule is not functional.
SELECT SCHEDULE_ID, [NAME]
WHERE ENABLED = 0 AND SCHEDULE_ID IN
(SELECT DISTINCT SCHEDULE_ID FROM MSDB..SYSJOBSCHEDULES)
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