Active Directory explorer - How can I search if a Group 'contains' a user?

In my Active Directory there is a Group "Gruppo Pippo", whit the attribute 'member'. 'member' contains many 'users':

CN=Alba Albi,OU=Developers,OU=Users,...

CN=Bianca Bianchi,OU=Partners,OU=Users,...

CN=Carlo Pony,OU=Developers,OU=Users,...

CN=Duilio Dorati,OU=Developers,OU=Users,...

I need a search that tell me if a user is contained in "gruppo Pippo".

I tried

(&(distinguishedName=CN=Gruppo Pippo,OU=DevOps,OU=Applications,OU=Groups,OU=Organization)(member=Pony))

but the constraint 'member contains Pony' doesn't run. (see image). Any suggestion? Thanks.

enter image description here

Solution 1:

The member= filter is incorrect. The value needs to be the value in the multivalued attribute, the distinguished name.

member="CN=Carlo Pony,OU=Developers,OU=Users,..."