Allow or prevent Automatic Forwarding/Replying to the Internet

Automatic Replies and Forwards buttonAs a secure default, on-premises Exchange doesn’t allow sending automatic forwards and automatic replies to the Internet.

This is mainly to prevent any unintentional mail loops, which users can create by using message rules in Outlook, which directly forwards the message to an external address or replies to the sender of the message with a template.

Exchange Online has advanced detection methods to prevent such mail loops and does allow automatic forwards and automatic replies to the Internet.

This article explains how Exchange Administrators can change this behavior via the Exchange Admin Center (ECP), Exchange Management Console (EMC) or Exchange PowerShell commands (EMS).

Exchange Online (Office 365)

Exchange Management Shell - PowerShellIn Exchange Online, you can adjust the Automatic Forward and Automatic Reply setting via the Exchange Admin Center.

Once logged on, select the Mail Flow section on the left and then the Remote Domains tab at the top.

Most likely, you only have one Remote Domain configured which is called “Default”.

Double-click this entry to adjust the configuration if needed.

Default configuration for the “Default” Remote Domain in Office 365.
Default configuration for the “Default” Remote Domain in Office 365.

Exchange 2013, Exchange 2016 and Exchange 2019

The Exchange Admin Center (ECP) for Exchange 2013 and Exchange 2016 does not expose the Remote Domain options in the Mail Flow section.

The only way to see or change the current configuration for automatic replying and forwarding to the Internet is via the Exchange Management Shell (EMS) with the PowerShell commands as explained below.

Exchange 2007 and Exchange 2010

When you are using Exchange 2007 or Exchange 2010, you can change the Automatic Forward and Automatic Reply settings via the Exchange Management Console (EMC).

  1. Open the Exchange Management Console.
  2. Expand Organization Configuration-> Hub Transport
  3. In the right pane select the Remote Domains tab.
  4. Right click Default and choose Properties.
  5. On the General tab you can set which type of Out of Office Messages you will allow to be sent out. By default only external OOF messages are allowed. You can change the option to also allow OOF messages created by Outlook 2003 and previous if you still need to support those clients (not very likely since they are out of support since April 2014).
    On the tab named “Format of original message sent as attachment to journal report:” (Exchange 2007) or “Message Format” (Exchange 2010) you can enable or disable the automatic replying/forwarding.

Allow automatic replies and forwards in Exchange 2010
Setting the option to allow automatic replies and forwards in Exchange 2010.

PowerShell (all Exchange versions)

Exchange Management Shell - PowerShellTo get the currently configured Remote Domains, use:

This usually only return a single result: Default.

To see the current configuration for this remote domain use:
Get-RemoteDomain Default | fl

In the result list, look for the settings for AllowedOOFType, AutoReplyEnabled and AutoForwardEnabled. You can directly filter your results list for these properties by using:
Get-RemoteDomain Default | fl AllowedOOFType, AutoReplyEnabled, AutoForwardEnabled

To change the settings, use the Set-RemoteDomain command.

  • Enable automatic replies
    Set-RemoteDomain -AutoReplyEnabled $true
  • Enable automatic forwards
    Set-RemoteDomain –AutoForwardEnabled $true
  • Enable OOF for Outlook 2003 and previous (for Exchange 2007 and 2010 support)
    Set-RemoteDomain –AllowedOOFType $ExternalLegacy

To change all these properties at once, you can use:
Set-RemoteDomain Default -AutoReplyEnabled $true –AutoForwardEnabled $true –AllowedOOFType $ExternalLegacy

Valid settings for the AllowedOOFType property are:

  • External
    This is the default and only allows for the new style OOF messages as introduced in Outlook 2007.
  • ExternalLegacy
    This settings allows for both the new style and old style OOF messages and needs to be set if you want to enable external OOF support for Outlook 2003 as well.
  • None
    This setting doesn’t allow for the use of OOF messages at all (both internal and external).
  • InternalLegacy
    This setting only allows for internal OOF messages to be sent for all Outlook versions.