Specifying Send As permission using PowerShell

For Exchange Online users, the master account from which Multimedia Contact Center retrieves emails requires Send As permission for the applicable distribution groups.

Before specifying Send As permissions, ensure that

A master account has been created in Exchange Online. This is the account from which Multimedia Contact Center will retrieve emails.
SMTP and IMAP or EWS connections to Multimedia Contact Center are configured.
Distribution groups are created for the contact center’s service groups.

To specify Send As permission for a distribution group using PowerShell

In Windows, open PowerShell.
To create the PowerShell connection to the remote Exchange Online, run the following credentials:
$LiveCred = Get-Credential

$Session = New-PSSession -ConfigurationName Microsoft.Exchange - ConnectionUri https://ps.outlook.com/powershell/ -Credential $LiveCred -AuthenticationBasic -AllowRedirection

Import-PSSession $Session
Enter the credentials for the Exchange Online administrator.
To add the Send As permission to the list
Add-RecipientPermission -Identity distributiongroup@example.com -Trustee mailbox@example.com -AccessRights SendAs

Note:
Identify corresponds to the distribution group. Trustee corresponds to the mailbox.
Repeat Step 3 for each distribution group.