Delegated Administrator

We have requirement to create Delegated Administrator who can manage only User and User Groups from CMC.(This group can only see only Users and User Groups tab in CMC):

Delegated Administrator Activities like Creating New Users,Groups,adding Users to User Groups etc

I have followed below steps

1.I have restricted CMC tabs access in Application tab by selecting Restricted rule in  CMC Tab Access Configuration.

2.Then created new group called Delegated Administrator Group and then added User to this group

3.Given View access  to Delegated Administrator Group in top level Security for All Groups

   Then Selected Delegated Administrator Group and then granted Access Explicitly to User and Usergroup in CMC Tab Access Configuration.

4. After Logged into CMC with the user account created in the above, I can see only Users and User Groups.This is working as expected.

    But I could not able to created new user or User Groups.

Please let me know if any one come across the Scenario.

Thanks,

Kumar