How do you know the entry is a duplicate?
You could use the find duplicates query wizard and reverse the query logic by
changing the criteria from IN to NOT IN. IT could be slow. You could also just
change the "Having Count(*) > 1" to "Having Count(*) = 1"
Query would look sopmething like.
SELECT *
FROM YourTable
WHERE SomeField IN (SELECT SomeField FROM YourTable GROUP BY SomeField HAVING Count(SomeField)=1)
Actually if you don't need the query result to be updatable then you might look
at a query like the following.
SELECT SomeField, AnotherField
FROM YourTable
GROUP BY SomeField, AnotherField
HAVING Count(*)=1
If duplicate is determined by several fields, then enter them and group by them.
