Cloudmark "blacklist" querying facility.


  • Hi guys,

    Numerous vendors and organisations maintain some kind of lookup facility where you can determine if a site is currently blocked, and perhpas in some instances trends such as for how long the block has been in place and the general reason for this being the case, yet I cannot find anything analagous to this for the Cloudmark service.

    Examples of what I'm talking about are sites such as:


    Does anyone know if there is such a function provided by Cloudmark or Microsoft? (I'm not really expecting the latter, but it's worth asking)


    Thursday, October 21, 2010 6:37 AM

All replies

  • so you want to know the reason why those services are blocking specific domain, am I right?!
    Regards, Mahmoud Magdy Watch Arabic Level 300 Videos about Exchange 2010 here: Read pretty advanced Exchange stuff I post here:, follow my blog: , corp blog:, Follow me on twitter and if you Liked my post please mark it as helpful and accept it as an answer
    Thursday, October 21, 2010 7:13 AM
  • No, not specifically - I was just using that as an example of what some sites provide. What I'm really after is proof that can be derived from a body external to ourselves that a remote domain has been classified as untrustworthy by Cloudmark.

    To be honest, this is more of a political issue. Right now, if a company has been "blacklisted" and therefore unable to send mail to us, usually the way we're notified is they complain to an executive at our university, who then proceeds to blame us, and the only place we can provide "proof" this isn't the case is from the Forefront output - which is obviously our own system. What we really need is the same kind of basic, external from either Microsoft or Cloudmark that we can send the external company and our own executives to so they can see for themselves that the classification has nothing to do with us and that we're not extracting misinformation from our systems to somehow cover the situation up.

    Something as fancy as wouldn't be necessary (though it would be nice), but something basic like the reporting from spamhaus would be ideal. So, what I'm asking is if such a facility already exists for Cloudmark/Microsoft Forefront for Exchange or not.

    All it boils down to is that external companies don't want to hear us telling them they have a problem. If we had an external reference to point them to that would go a long way to helping them understand they need to fix up things like invalid or missing SPF information; invalid sending domains (we've had numerous instances where people have the actual server as the sending domain), etc.

    Also, it just occurred to me I've posted this in the Exchange forums, where technically it should have been on the Forefront forum, even though it's about Forefront for Exchange - my mistake. If the thread can be moved, I'd appreciate it.


    Thursday, October 21, 2010 7:40 AM
  • Hi Lain,

    When Forefront rejects an email (as the domain is blacklisted), the sender will get a bounce back with the company that has the domain in the blocklist and an advice to contact them to get it sorted.

    Isn't your sender getting a bounce with a similar message?

    Rajith Enchiparambil | |

    Thursday, October 21, 2010 8:04 AM
  • Hi Rajith,

    Not that I've seen to date, no. The only examples I've had forwarded to me thus far have all been simplistic NDRs of the 5.7.1 variety (rejected due to content restrictions).


    Thursday, October 21, 2010 8:44 AM
  • Disappointing, but that's what I was expecting the answer might be. Thanks for the answer though, Troy.


    Thursday, October 21, 2010 11:33 PM
  • I found this thing that seems to lookup IPs listed on CloudMark. Not sure who is hosting it, but I definitely get some IPs listed in there as being on Cloudmark's Blacklist. 


    Friday, February 25, 2011 11:03 PM
  • So can you share this mythical cloudmark checking link with us? ;)
    Wednesday, April 27, 2011 11:29 PM
  • use this

    Friday, March 02, 2012 7:23 PM
  • Hi! Have you found the solution for this yet? :) I am on the same dead end at the moment, but maybe you have solved that, and maybe could help. Would be awesome!
    Friday, September 05, 2014 7:31 AM
  • Hi Lain sure, Cloudmark have the following CSI IP Reputation Remediation portal  it's called Cloudmark Sender Intelligence, it's a comprehensive global sender monitoring and analysis system that delivers timely and accurate reputation on good, bad, and suspect senders.

    Also you can use it to clear the effected IP.

    Mahmoud Hanafi

    MCITP, MCSE, Technology Expert.

    • Edited by Mahmoud.Hanafi Saturday, November 15, 2014 4:31 PM Amendment of the comment
    • Proposed as answer by mahmoudshoaala Wednesday, June 24, 2015 9:49 AM
    Saturday, November 15, 2014 4:19 PM
  • So, apparently, there is no such a thing as presumption of innocence: everyone can block anyone without any shred of proof. Did I say proof? I beg your pardon, proof has nothing to do with the blocking - servers get blocked just for the heck of it - and, somehow, it's solely your job to clear your name. Oh thank you for providing this link! I guess when you and your family members get arrested and put to prison randomly, you will not feel abused or betrayed since you will be getting a chance to appeal, right? :) I don't want to live in your world, sir!

    P.S. People who install or use software like Cloudmark CSI, but says "blocking has nothing to do with me" are the same as the ones who say "People don't kill people - bullets and knives kill people" :)

    Friday, August 05, 2016 5:07 PM