Create and Save the Sort Spec in Preview Mode.
Save Name as "DateCompleted, Desc." or whatever is correct for you.
Now go back to Report Designer and assign that stored Sort Spec to the report.

In the Commands at the top click on "Attach Specs"
In Spec Type, select "Sort Spec"
In Attach Spec, select "Select a Different Spec"
In Select A Spec, select the Sort Spec that you saved earlier, "DateCompleted, Desc."
Click on Attach button, Close Window.
Save Report design.

Note:  Once a Spec is attached to a report, the user cannot change the sort at run time.  If you have sorted the result set by customer for example, and run the report, it will be sorted by DateCompleted not by Customers.
You may want to consider not attaching a spec, but making some type of Sort Picklist to choose from at run time.  That way, one report can serve many functions, vs. having a special report for every sort criteria.

Hmmm, did I just hear a sneeze?  God Bless You!.
Take care of your headcold.


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Reminder, when you reconcile, you will probably want the Saved Specs to replace the ones in the normal Database.  If not, you will want to reconcile to get the report design done, then open the normal database and save the Sort Spec under the same name as used in the Preview Mode. 

Only you can determine whether or not to replace the Saved Specs. 
Just wanted to remind you of the issue.

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Edited.  As noted below by Erika, these steps do not need to happen.  My reminder here was not actually needed.  Sorry about that.

AHA!....I never realized that. 

That will save me many steps, wish I realized that earlier. 

Thanks Erika!

Quote:

Hokey smokes, I never knew that.  I have some cleaning up to do.