Active Directory contacts include information about a person or business, such as phone numbers, email addresses, and fax numbers. Creating and managing AD contacts is vital for organizations, as contacts can be listed in a Global Address List (GAL) or another address list, allowing users to access contact information and send messages. For a brief overview on the differences about Active Directory user account and contact, see https://techdirectarchive.com/2020/04/09/difference-between-a-contact-and-a-user-object/

Why would you want to create a contact in Active Directory (AD)?

– Contact is most times needed in AD when you have a member that is not a regular user in your organization, such as an external (3^rd party contractor). This will ensure a user account is not created for the user.
– Contact accounts will also help maintain a high level of security in your organization.
– Lastly, it will help save contact and help email software access the contact details.

Note: Contact only contains details about a person and does not contain the SID enabled on the user
Noe: This is similar to contacts in O365

Create a contact in Active Directory
– Under Tools,
– Launch Active Directory Users and Computers

Right-click on the OU, where you want the contact to be created.
– Click on New
– Click on Contact

And follow the dialog box displayed to perform the tasks.

When you have it created here, there is no need creating it again an Exchange Server as the exchange server will be able to access the details.

– To configure additional properties
– Right-click on the contact and select properties

Note: You can add the contact to the group etc., despite not having a SID.
Because it does not have the SID enabled, they are not granted access to the group they belong to but only on getting emails sent to the group they belong to.