As per previous notices, Microsoft has changed the behavior of its inbound connector. This notice is now marked as complete, but the links to instructions for DLP customers will remain in the link provided:
https://knowledge.broadcom.com/external/article?articleId=275421
Reminder:
To avoid any issues, Symantec Data Loss Prevention has created a set of instructions you can use to address this upcoming change. Symantec Data Loss Prevention Cloud Service for Email Reflecting mode customers will be required to make some configuration changes based on these instructions.
Reminder:
To avoid any issues, Symantec Data Loss Prevention has created a set of instructions you can use to address this upcoming change. Symantec Data Loss Prevention Cloud Service for Email Reflecting mode customers will be required to make some configuration changes based on these instructions.
Reminder:
To avoid any issues, Symantec Data Loss Prevention has created a set of instructions you can use to address this upcoming change. Symantec Data Loss Prevention Cloud Service for Email Reflecting mode customers will be required to make some configuration changes based on these instructions.
Reminder:
To avoid any issues, Symantec Data Loss Prevention has created a set of instructions you can use to address this upcoming change. Symantec Data Loss Prevention Cloud Service for Email Reflecting mode customers will be required to make some configuration changes based on these instructions.
Issue
Microsoft is changing the behavior of its inbound connector. You can find details about this change from Microsoft at Updated Requirements for SMTP Relay through Exchange Online.
This change only impacts Symantec Data Loss Prevention customers using Symantec DLP Cloud Service for Email in Reflecting mode. Due to these changes, emails sent with a null sender are rejected when delivered back to Microsoft 365.
Resolution
To avoid any issues, Symantec Data Loss Prevention has created a set of instructions you can use to address this upcoming change. Symantec Data Loss Prevention Cloud Service for Email Reflecting mode customers will be required to make some configuration changes based on these instructions.
If you have questions or require assistance, contact Broadcom Technical Support. We will provide additional updates as new information becomes available.
Make the required configuration changes outlined in the Knowledge Base article.