Unless there's a problem with your "cut & paste", you did not make the change I proposed. Verified and working here: exten => 8600,50,Set(CALLERID(num),2000) exten => 8600,51,VoicemailMain(${CALLERID(num)}|s) Notice how VoiceMailMain also uses ${CALLERID(num}, not ${CALLERIDNUM}