Procedure for whitelisting the e-securemail IP

Check permissions by IP address in Microsoft 365 :

In order to bypass SPF checks, we strongly recommend that you enter our IP range on the tenant Office. This improved filtering will allow to bypass the e-securemail IP as the legitimate sending server of the sender and avoid the errors visible in the headers (SPF error, because it takes as sending server, for example, the domain example.com, an IP of e-securemail that does not match their SPF). This results in a wrong categorisation of the email in the user's inbox.

1. Go to the M365 security portal - https://security.microsoft.com/
2. Open Email & Collaboration in the left sidebar and go to Policies & Rules > Threat Strategies > Anti-Spam Software
3. Click Connection Filter Policy, then click Change Connection Filter Policy in the drop-down menu

4. Add the following IP addresses to the Always allow messages from the following IP addresses or address range field

For the IP Ranges to be filled in, please contact our support department at support@secuserve.com.

Practical link: https://docs.microsoft.com/en-en/exchange/mail-flow-best-practices/use-connectors-to-configure-mail-flow/enhanced-filtering-for-connectors

Bypassing Microsoft 365 Filtering:

This guide helps you address instances where some of your messages are categorized as "junk mail."

It is possible that a Microsoft 365 tenant belonging to one of our clients categorizes incoming messages as "junk mail." This behavior is due to checks performed by the Microsoft 365 tenant, including SPF verification (which is bound to fail).

Useful Link:
Use Connectors to Configure Mail Flow with Enhanced Filtering

Spam Confidence Level (SCL):
Learn About Spam Confidence Level (SCL)

Go back to the Admin Center and click on Exchange.

1. Go to the Mail Flow section and Rules, then add a rule to "Bypass spam filtering."

2. Name the rule and select "Apply this rule if > The sender > The IP address is in any of these ranges or exactly matches."

 3. Add our IPs. (Contact support@secuserve.com to obtain the IP ranges.)  

 Select "Do the following… Modify the message properties… > Set a message header."

4. Modify the "Text Entries":

Assign the first text as "X-MS-Exchange-Organization-BypassClutter".

Assign the second text as "true".

Then,

5. Add an action and select "Modify the message properties… > Set the spam confidence level (SCL)".

Select Bypass filtering to apply -1.

 6. Then click Next and Apply the rule to complete.  

Next and Finish to save.

Declare the Microsoft Tenant:

Activate the Tenant-ID.