Often when you run the duplicate search merge you will be presented with records that aren't really duplicates. You can mark those as "Not a match" on the merge screen so that RootsMagic doesn't keep presenting them as possible duplicates. The "Not Duplicates" list displays items you marked as "Not a match" on the merge screen.
To see what "non-duplicates" RootsMagic is ignoring:
•Select the People view, then select Tools > Merge > Not Duplicate list from the menu

•Click the "Remove from 'not duplicates' list" button – to remove the selected pair from the Not Duplicates list so that Duplicate Search can consider it again.
•Click Close to close the dialog.
Reconsider an excluded pair
Remove a pair from this list when you want Duplicate Search to consider it again. Removing the exclusion neither deletes a person nor merges the pair. Run Duplicate search merge again and review the evidence before deciding what to do.