This used to work in older version, does not work in 599 r2

If this was not supposed to work due to an error, how to re-write.
If it is valid, can you please fix.

error: Column references must either be in aggregate functions or grouped on C.ClientID

Regards,
Scott.

SELECT C.ClientID,MIN(C.DisplayName) AS DisplayName FROM Clients C
LEFT JOIN ClientRolodex CR ON (C.ClientID = CR.ClientID)
INNER JOIN Rolodex R ON (CR.RolodexID=R.RolodexID)
WHERE R.Description = 'Seminar Attendee'
AND
NOT EXISTS (
SELECT C.ClientID,MIN(C.DisplayName) AS DisplayName FROM ClientRolodex bCR
INNER JOIN Rolodex R ON (bCR.RolodexID=R.RolodexID)
WHERE (bCR.ClientID = C.ClientID)
AND R.Description = 'Client - Dan'
)
GROUP BY C.ClientID

Oh my ... wrong NG, wrong product ... oops.

Please cancel/disregard post.

Regards,
Scott.