Emails to certain domains are getting hung in the Queue

Posted on 2011-04-22
Last Modified: 2012-05-11
Ok, first things first.

We had a Reverse NDR Attack last week and was put on a couple of Blacklists. I have cleared our IP's from all of the known blacklists I can find at On top of all of that Yahoo is giving me the 4.7.1 error which I'm currently going through the hoops I have to jump to get us cleared through them.

With all of that said...

Domains such as the following are hanging in our Queue and it just seems odd to me that some of these are getting hung.

I can see the above getting stopped in queue because they are probably one way or another related to Yahoo but the following I just find it odd they are getting hung.

On top of that... If I send an email from yahoo to our domain it goes through without a hitch, but I've been told by people who are trying to send us email from MCHSI (Mediacom) that they are getting an error back when trying to send to us.

Does anyone have any suggestions for me on this?  I need new leads!  

Thank you in advance
Question by:Rmumpower00
    LVL 27

    Expert Comment

    firstly, incoming messages:
    Incoming messages are not affected at all by blacklists etc. if inco,ing messages from some companys are having trouble you need to investigate why. any chnages you have made to stop another ndr attack could be related.

    Outgoing messages.
    Yes it is likely to be linked but you need to test it to confirm.

    try to send a test email manually form your email server and see what the receiving servers actually say.

    Author Comment

    To send a test email manually from the email server do I just type in a command prompt:

    telnet <validpersonsemail> 25
    LVL 27

    Accepted Solution

    follow the link provided above for step by step instructions.

    Author Closing Comment

    I still can't email to yahoo but for the most part the others are clearing up as time passes.

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