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MX Lookup Mail Server Domain by Email Address

How to find the mail server for a given email address. Returns the domain name of the primary mail server.

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Local $bSuccess = False

; This example requires the Chilkat API to have been previously unlocked.
; See Global Unlock Sample for sample code.

$oDns = ObjCreate("Chilkat.Dns")
$oJson = ObjCreate("Chilkat.JsonObject")

Local $sEmailAddr = "bob@example.com"

; This gets all MX domains for an email address.  (Typically one domain.)
; The preferred domain will be at index 0 (see below).
$bSuccess = $oDns.Query("MX",$sEmailAddr,$oJson)
If ($bSuccess = False) Then
    ConsoleWrite($oDns.LastErrorText & @CRLF)
    Exit
EndIf

Local $i = 0
Local $iCount_i = $oJson.SizeOfArray("answer.mx")
While $i < $iCount_i
    $oJson.I = $i
Local $sDomain = $oJson.StringOf("answer.mx[i].domain")
    ConsoleWrite($sDomain & @CRLF)
    $i = $i + 1
Wend