Not really what I wanted, but thanks, it is much more complicated than an advanced filter

The criteria is as follows

ID1 is linked to one+ ID2's, no single ID2 can be linked to the same ID1 more than once, but an ID2 can be linked to two different ID1's, for example

ID1 ID2 RESULT
1 A DUPLICATE
1 A DUPLICATE
1 A DUPLICATE
2 B NOT A DUPLICATE
2 C NOT A DUPLICATE
3 C NOT A DUPLICATE
4 D DUPLICATE
4 D DUPLICATE

Is there there away to automate this as I have a huge data set to apply this to so manual checks is out of the question

If anyone can help please help