Wednesday, December 31, 2014

How to send more than one out of office reply

In the Microsoft Exchange environment, there is a feature called Out Of Office message. Called OOF for short it's an automatic reply with the information that the recipient is currently absent. It usually contains the information when the user would be back in the office, who to contact in the case of urgent matters and sometimes the reason of the absence. It is a common practice and in a good tone to let the sender know that the message was, in fact, received but the response would be delayed.

This feature however contains a limitation - the OOF message is sent only once to the specific email address. On one hand, it prevents the server from engaging in the "auto replies war" or "auto reply storm" when automatic responses are sent back and forth indefinitely. On the other hand, if the sender's email address is utilized by multiple users (e.g. team mailboxes) the OOF message might not reach all of them causing confusion.

The official solution proposed by Microsoft in their KB article ( is to use the transport rules features instead. Unfortunately, it poses the already mention threat of the "auto replies war".

Another solution is to reset the OOF state by disabling and then enabling it again on the e.g. daily basis. You can check the OOF status of the given mailbox with the following PowerShell cmdlet:

Get-MailboxAutoReplyConfiguration -Identity Luke

To disable the autoreply on the selected mailbox use the "set" cmdlet:

Set-MailboxAutoReplyConfiguration -Identity Luke -AutoReplyState Disabled

To enable it again use the same command but with a different parameter:

Set-MailboxAutoReplyConfiguration -Identity Luke -AutoReplyState Enabled

A full script that resets the OOF state for all users that are currently using it goes as follows:

$OOFActive = get-mailbox -resultsize unlimited |get-mailboxautoreplyconfiguration | where {$_.autoreplystate -eq "enabled"} | select identity,autoreplystate 

$enabled | foreach-object { set-mailboxautoreplyconfiguration $_.identity -autoreplystate "Disabled" set-mailboxautoreplyconfiguration $_.identity -autoreplystate $_.autoreplystate }

Unfortunately, you need to remember to run the above script on a daily basis.

To overcome all of the above limitations you can use a third party app, such as MSH Exchange Autoresponder from MSH Software. Among other features it contains a configurable loop protection that prevents the "auto reply storm" and allows to send more than just one OOF message to the same recipient. Moreover, you can set up recurring timeframes for the Out Of Office reply, and use a WYSIWYG editor to create the message itself which is quite useful as both of these features are not present in the native OOF assistant on the Exchange server. The program works automatically and you do not need to use any scripts. 

Download the fully functional trial of the MSH Exchange Autoresponder app from the following location: