To request to whitelist a domain on Microsoft email services you can follow these simple steps.
First, check the spamicity of your email.
You can use http://www.mail-tester.com/
Please consider Using SPF and DKIM.
If you didn't set up your domain DNS please go under your Project Settings -> Email -> Outbound.
If your result is above 9, you can browse this page to check the status of your server:
https://sendersupport.olc.protection.outlook.com/snds/
Enter your server's IP and follow instruction.
If your IP is blacklisted, you have to open a case here:
https://support.microsoft.com/en-us/supportrequestform/8ad563e3-288e-2a61-8122-3ba03d6b8d75
Fill in the fields and in a few minutes you will receive a receipt of the request, then later on a validation (or not) of the setting in whitelist with the period of observation.
If your request is accepted, it will take a few hours to a few days for Microsoft servers to be up to date.
