DOCUMENT:Q198551  10-AUG-2001  [winnt]
TITLE   :NSLOOKUP Returns Time-out Error When Query for an MX Record
PRODUCT :Microsoft Windows NT
PROD/VER:winnt:4.0,4.0a
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Windows NT Server, Enterprise Edition version 4.0 
 - Microsoft Windows NT Server version 4.0 
 - Microsoft Windows NT Workstation version 4.0 
 - Microsoft BackOffice Small Business Server versions 4.0, 4.0a 
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SYMPTOMS
========

If you use Nslookup.exe to query for a Mail Exchanger record (MX), it may fail
with the following error:

   *** Request to <dnsserver.example.microsoft.com> timed-out

NOTE: <dnsserver.example.microsoft.com> is the host name of the DNS server
you are querying.

CAUSE
=====

If the DNS server that you are querying has an MX record in the DNS zone similar
to

   domainname.example.microsoft.com.    MX    10    192.168.1.1

you may see the error mentioned above.

RESOLUTION
==========

Change the MX record to point to a host name that will then, in turn, resolve to
the same IP address. For example, in the domainname.com zone, make the following
change:

   domainname.example.microsoft.com. MX 10 host1.domainname.example.microsoft.com
   host1                             A  192.168.1.1

STATUS
======

This behavior is by design. According to RFC 974:

   Each MX matches a domain name with two pieces of data, a preference value (an
   unsigned 16-bit integer), and the name of a host.

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Keywords          :  
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400 kbWinNTS400search kbWinNTS400 kbAudDeveloper kbSBServSearch kbSBServ400 kbSBServ400a
Version           : winnt:4.0,4.0a
Issue type        : kbprb

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