Let's give the Contacts Administrator permission to log in to the backend:
Go to System | Global Configuration and click the Permissions tab. Select the Contact Administrator user group. The permissions for the group are shown.
For this group, change the Admin Login permission to Allowed:
If you were to log in to the site as a Contact Administrator now, you'd be able to access the backend, but there would hardly be any functionality available at all—you'd just see the backend interface with just a few menu options (allowing you to edit your account profile).
So now that we've set the proper permissions on a site-wide level, it's time to set more specific permissions. We have to allow our new group to actually manage contacts in the backend. To do this, we customize the permissions of the Contacts component.
Go to Components | Contacts and click the Options button.
Click on the Permissions tab to change permissions to Allowed for this...