Just an aside for those who still have 2003 version recipients I have a VB script that allows me to do this very thing:
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Set objMAPISession = CreateObject("MAPI.Session")
strExchangeSvr = InputBox("Please provide the name of your Exchange Server")
strMailbox = InputBox("Please provide the name of the Mailbox that you wish to set OOO")
strMAPI = strExchangeSvr & vbLf & strMailbox
On error Resume Next
objMAPISession.Logon "", "", False, True, 0, False, strMAPI
If err <> 0 Then
Wscript.Echo "An Error occured: " & err.description
Err.clear
Wscript.Sleep 7000
Wscript.Quit
End If
strOOOMessage = InputBox("Please type in the OOO message for this user")
objMAPISession.OutOfOfficeText = strOOOMessage
objMAPISession.OutOfOffice = 1
strOOOMessage = objMAPISession.OutOfOfficeText
objMAPISession.Logoff
Set objMAPISession = Nothing
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