Envelope.ReturnAddress (Word)
Returns a Range object that represents the envelope return address.
An error occurs if you use this property before adding an envelope to the document.
On Error GoTo errhandler
addr = ActiveDocument.Envelope.ReturnAddress.Text
MsgBox Prompt:=addr, Title:="Return Address"
errhandler:
If Err = 5852 Then MsgBox _
"The active document doesn't include an envelope"