Originally it looked as follows:)
Dear, Just Me!
There some of possible reasons for this response are:
– called subscriber is absent in HLR, or
– routeing table in your (most likely) MSC does not contains the routeing … for called subscriber number, or
– (if home called subscriber is in roaming) routeing table in your (most likely) MSC does not contains the routeing … for Routeing number (MSRN) from the called subscriber current visited network.