Mail Assure Troubleshooting
Mail AssureMicrosoft 365 Header Based Configuration
Last Modified
Sun Apr 12 22:46 GMT 2020
Description
- Looking to configure Microsoft 365 with Mail Assure
- IP based restrictions is not ideal as IP addresses can only be added one at a time
- Looking to use header based restrictions
Environment
- Mail Assure
- Microsoft 365
Solution
- To restrict deliveries to your Office365 server(s) using Header based restrictions, use the Mail-flow rules to reject messages that do not have your SpamExperts headers
- For header based rejections, you will need to set two rules:
- Rule 1:
- Select Admin and choose Exchange from the menu
- Select Mail Flow
- Under Rules, click the +button and choose Create New Rule
- Add a Name for your Rule
- For example: "Disable SpamFiltering and accept from SpamExperts"
- Select More Options
- Create Rule "A message header includes "X-Recommended-Action" header includes >> "accept"
- Select the + option
- Select OK
- In the "Do the following" part, select "Modify the message properties" >> "Set the spam confidence level (SCL)" >> "Specify SCL" >> "Bypass spam filtering"
- Select OK
- Enable Enforce from the rule mode
- Check the Stop processing more rules box
- Select Save
- Rule 2:
- Select Admin and choose Exchange from the menu
- Select Mail Flow
- Under Rules, click the +button and choose Create New Rule
- Add a Name for your Rule
- For example: "Reject Direct Deliveries"
- Create Rule "[Apply to all messages]"
- In the "Do the following" part, select "Reject the message with the explanation" and add something along the lines of "Did not deliver via Antispam Provider"
- Enable Enforce from the rule mode
- Select Save
- Rule 1:
- Once setup correctly, you need to make sure the rules are in the correct order
- Messages that are now delivered directly and not via the filtering nodes will be rejected with:
- 550 5.7.1 TRANSPORT.RULES.RejectMessage; the message was rejected by organization policy
- For more information on this, please go here