I can't rival the other guys on this board, but I am using this as practice for myself and would like (constructive but friendly) feedback on the solution I came up with if anyone is willing. 🙂

WITH CTE1 AS

(

SELECT IPCode, ID

FROM [Profile]

GROUP BY IPCode, ID

),

CTE2 AS

(

SELECT IPCode

FROM CTE1

GROUP BY IPCode

HAVING COUNT(*) > 1

)

SELECT IPCode, ID

FROM [Profile]

WHERE IPCode IN

(SELECT IPCode FROM CTE2)

GROUP BY IPCode, ID