Toggle - Direct Connect to Office365 Feature Param

Summary

Microsoft launched the “Direct Connect to Office365 Feature” (Outlook 2016 version 16.0.6741.2017 and higher) that forces Outlook 2016 to connect to Office365 when:

• Users are not yet active in Office365 and do not have a mailbox provisioned due to the Exchange license assigned.
• Autodiscover is not working on the source server.
• The connection between the computer and the source server is interrupted or blocked by a firewall/antivirus.

This feature is beneficial as it automatically detects your Office365 account; however, it can also pose significant problems during the migration process to Office365.

When this occurs, email continues to work; however, the user will not receive any emails in Outlook since it is connected to Office365; they will receive them on their respective source server.

See this article for more information about the “Direct Connect To Office365” Feature: Unexpected Autodiscover Behavior

The script can be used to create a user-level registry key for all users to prevent this behavior or to reset it back to normal.

Please ensure that the "ExcludeExplicitO365Endpoint" parameter has the correct value. A value of 1 will "Prevent Outlook from Connecting to an Office 365 Account," while a value of 0 will "Allow Outlook to Connect to an Office 365 Account."

Sample Run

Variables

Name	Description
OutCome	Output of the PowerShell script writing the registry value

User Parameters

Name	Example	Required	Description
ExcludeExplicitO365Endpoint	1	True	Represents the action you would like to perform with the script. A value of 1 will "Prevent Outlook from Connecting to an Office 365 Account," while a value of 0 will "Allow Outlook to Connect to an Office 365 Account."

Process

1. Verify the value passed to the ExcludeExplicitO365Endpoint parameter.
2. Execute the PowerShell script to modify/add the registry key.
3. Log the output of the script.

Output

Script Log

Changelog

2025-04-10

• Initial version of the document