NDR, Your mail system could not find a way to successfully communicate with the destination system

Posted on 2009-02-18
Last Modified: 2012-05-06
I just need to confirm what I am think since this I am only at mid level with exchange.  I have an invidual that here that sent and e-mail message that he was able to send to before that received and NDR that states.  

External} on 2/17/2009 5:12 PM
            Your mail system could not find a way to successfully communicate with the destination system. Please notify your administrator.
            <FS-Mail.ERB.local #5.5.2 smtp;502 5.5.2 Error: command not recognized>

He was e-mailing

When looking at the mx record I saw the following.

5 86400  
6 86400  
7 86400  
10 86400  

I tried telneting into each one to test but couldnt even get a helo response.  The doesnt even seem to exist.

Any and all help is appreciated.
Question by:dplaw
    LVL 18

    Expert Comment

    can you try re-send? I just checked the mx records, at least the last one is accepting emails.

    Author Comment

    So it does appear that the top weighted 3 are not accepting e-mailsat this time correct?  How did you verify that the last one is accepting at this time?  And yes, I will ask the user to try again.
    LVL 18

    Accepted Solution

    I used the following website

    Author Comment

    Thank you.  Just a quick follow up question, it mentions that it may be greylisting, how does that effect my domain and the one your ran the test from and what does it mean?
    LVL 18

    Assisted Solution

    greylisting is a way to fight spam. it means
    "A mail transfer agent (MTA) using greylisting will "temporarily reject" any email from a sender it does not recognize. If the mail is legitimate, the originating server will try again and the email is accepted. If the mail is from a spammer it will probably not be retried since a spammer goes through thousands of email addresses and can not afford the time delay to retry."

    Your server should retry if the first try failed, then if the recipient's email think it's legetimate, it will receive.

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    Are end users causing IT problems again?

    You’ve taken the time to design and update all your end user’s email signatures, only to find out they’re messing up the HTML, changing the font and ruining the imagery. What can you do to prevent this? Find out how you can save your signatures from end users today.

    Use these top 10 tips to master the art of email signature design. Create an email signature design that will easily wow recipients, promote your brand and highlight your professionalism.
    ADCs have gained traction within the last decade, largely due to increased demand for legacy load balancing appliances to handle more advanced application delivery requirements and improve application performance.
    In this video we show how to create a User Mailbox in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Recipients >> Mailb…
    how to add IIS SMTP to handle application/Scanner relays into office 365.

    760 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    12 Experts available now in Live!

    Get 1:1 Help Now