Log into your mail server admin portal and go into the Admin -> Exchange area.
Click on Admin -> Exchange.
Click on Connection Filter (beneath Protection heading).
Click on Connection Filter, then click the Pencil icon to edit the default connection filter policy.
Under the IP Allow list, click the + sign to add an IP address.
Click OK, then Save. Next, you will want to set up a mail flow rule to allow our mail to bypass spam filtering and the Clutter folder.
To ensure our messages will bypass your Clutter folder as well as spam filtering within Microsoft’s EOP, you can follow the steps below.
Go to Admin -> Mail -> Mail Flow.
Click the (+) Create New Rule button beneath Mail Flow -> Rules.
Set the message header to this value:
Set the message header “X-MS-Exchange-Organization-BypassClutter” to the value “true“.
Add an additional action beneath “Do the following” to “Modify the message properties”. Here, click on “Set the spam confidence level (SCL) to…” and select “Bypass Spam Filtering”.
Click Save. An example of the completed rule is below.