Problem:

I want to edit my scheduled jobs, but for some jobs this is not possible.

Answer:

A while ago DC Job was redesigned. Scheduled jobs that were created in the new DC Job can be edited, but older scheduled jobs, that were created in the old DC Job, cannot be edited. 
Instead, create a new scheduled job, and deactivate or delete the old one.

To edit, (de)activate or delete scheduled jobs: 

1. Go to the DC Job tab.
2. Click the Down arrow next to the Job Overview header to switch to the Scheduled Job Overview. 
   
   The Scheduled Job Overview opens.
3. Find the job and click Job Options at right.