Log into your Microsoft 365 Exchange Admin Center using your Microsoft 365 login credentials. You can access this at https://outlook.office365.com/ecp
Click on mail flow in the left navigator then on connectors at the top
Create CrosswareInboundConnector
Select
From: Your organization's email server
To: Microsoft 365
You need to enter the following text:
Connector Name: CrosswareInboundConnector
Certificate Name: *Your Unique Certificate copied from the Crossware Portal*
Review, verify, and turn the connector on