To set up out of office messages by using Exchange 2010 PowerShell, run the following cmdlet in the Exchange PowerShell window to configure detailed information about the out of office message setup:
Set-MailboxAutoReplyConfiguration <alias> -AutoReplyState enabled -ExternalAudience all -InternalMessage <Message to internal senders> -ExternalMessage <Message to external senders>
Set-MailboxAutoReplyConfiguration John -AutoReplyState enabled -ExternalAudience all -InternalMessage "Please note, John Smith no longer works with the Company </br></br> Please contact our office on 03 9999 9999 </br></br> Thank You" -ExternalMessage "Please note, John Smith no longer works with the Company </br></br> Please contact our office on 03 9999 9999 </br></br> Thank You"
