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How can hotmail be blacklisted by Spamhaus RRS feed

  • Question

  • Hi,

    The last 4 weeks or so hotmail messages sent to our domain do not get delivered.

    This is the NDR code hotmail users receive :

    Diagnostic-Code: smtp;550 5.7.1 Recipient not authorized, your IP has been found on a block list

    When I check the antispam logs on our Exch 2007 it mentions indeed hotmail IP addressess that are blocklisted by Spamhaus.

    How can I resolve this ? How can a mail system of that magnitude get blocklisted ?

    I tried adding the domain *@hotmail.com to the exceptions list on the Block list tab in exchange but that didn't help.

    Friday, September 10, 2010 7:20 AM

Answers

  • On Fri, 10 Sep 2010 07:20:16 +0000, miauwington wrote:
     
    >
    >
    >Hi,
    >
    >The last 4 weeks or so hotmail messages sent to our domain do not get delivered.
    >
    >This is the NDR code hotmail users receive :
    >
    >Diagnostic-Code: smtp;550 5.7.1 Recipient not authorized, your IP has been found on a block list
    >
    >When I check the antispam logs on our Exch 2007 it mentions indeed hotmail IP addressess that are blocklisted by Spamhaus.
    >
    >How can I resolve this ?
     
    Stop using spamhaus?
     
    >How can a mail system of that magnitude get blocklisted ?
    You'd have to ask the people that manage that DNSBL.
     
    >I tried adding the domain *@hotmail.com to the exceptions list on the Block list tab in exchange but that didn't help.
     
    Add the IP addresses to the IP Allow List. Whitelisting a domain name
    like hotmail.com is just asking for trouble.
    ---
    Rich Matheisen
    MCSE+I, Exchange MVP
     

    --- Rich Matheisen MCSE+I, Exchange MVP
    • Marked as answer by miauwington Monday, September 13, 2010 8:29 AM
    Saturday, September 11, 2010 12:23 AM

All replies

  • A second, related question that comes to mind :

    How can I check the last time the exchange antispam agents successfully updated ?
    When I type "Get-antispamupdates", all I get is a bunch of numbers, like LatestIpReputationVersion 3.3.950.etc.

    Friday, September 10, 2010 7:41 AM
  • On Fri, 10 Sep 2010 07:20:16 +0000, miauwington wrote:
     
    >
    >
    >Hi,
    >
    >The last 4 weeks or so hotmail messages sent to our domain do not get delivered.
    >
    >This is the NDR code hotmail users receive :
    >
    >Diagnostic-Code: smtp;550 5.7.1 Recipient not authorized, your IP has been found on a block list
    >
    >When I check the antispam logs on our Exch 2007 it mentions indeed hotmail IP addressess that are blocklisted by Spamhaus.
    >
    >How can I resolve this ?
     
    Stop using spamhaus?
     
    >How can a mail system of that magnitude get blocklisted ?
    You'd have to ask the people that manage that DNSBL.
     
    >I tried adding the domain *@hotmail.com to the exceptions list on the Block list tab in exchange but that didn't help.
     
    Add the IP addresses to the IP Allow List. Whitelisting a domain name
    like hotmail.com is just asking for trouble.
    ---
    Rich Matheisen
    MCSE+I, Exchange MVP
     

    --- Rich Matheisen MCSE+I, Exchange MVP
    • Marked as answer by miauwington Monday, September 13, 2010 8:29 AM
    Saturday, September 11, 2010 12:23 AM