I tried to use Both of them: the ROUTE method and the SENDMAIL method.
I used this macro:

Sub POSTA()
With ActiveDocument
   .HasRoutingSlip = True
   With .RoutingSlip
       .Delivery = wdOneAfterAnother
       .AddRecipient xxx@xxx.it
       .Subject = "Here is the document"
       .Message = "Greetings..."
       .ReturnWhenDone = True
   End With
   .SendMail (or .Route)
End With
End Sub

WORD writes:
RUN-TIME ERROR 4605 - you have MAIL not installed...      WHAT IS MAIL? Why
i can use the manual command, and it asks me MAIL in my macro?