Has anyone used a workflow to catch duplicate sales orders? I would love to flag orders with the same PO number.

Maybe use a simple saved search Like in result: group transaction name and use count on internal Id field If the count are greater than 1 you can catch the duplicate

Hmm, I have something very similar already, but I'm looking for something more precise

I think that a search of this type will be very precise because you will know exactly how many times an SO with the same reference has been used

In my saved search, I look for the duplicates and sort by count of document number and it should always be 1. The issue is that I want a saved search that shows me ONLY the duplicates, and not every PO ever (or limited by date filter).

You can use a summary search filter

Don’t use count on Document number Use count on internal id Criteria : type = sales order And Main line is true Criteria summary : count on internal id is greater than 1 Result : Group by Transaction name / document number Count by internal Id