Information
You can use this setting to determines if the server automatically sends delivery reports to remote domains.
Rationale:
Attackers can use automated messages to determine whether a user account is active, in the office, traveling, and so on. An attacker might use this information to conduct other types of attacks.
Solution
To implement the recommended state, execute the following PowerShell cmdlet:
Set-RemoteDomain -Identity Contoso -NDREnabled $false