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MisterAG
MisterAG
New Member
May 28, 2010
Question

smtp helo/ehlo domain name DNS check failed

  • May 28, 2010
  • 2 replies
  • 7361 views
Can anyone point me in the general direction of what causes this error message? smtp helo/ehlo domain name DNS check failed. Starting last night, thousands of legitimate email was being blocked at the Fortigate. I have since disabled antispam protection on the Fortigate, and am now trusting our Barracuda to do the job on its own. Is this the Fortigate checking that the EHLO banner and dns hostname both resolve to the same IP address for the sending mail server?

    2 replies

    discoveryit
    discoveryit
    New Member
    May 28, 2010
    disable Return e-mail DNS check and HELO DNS lookup in the Email Filtering in your protection profiles.
    MisterAG
    MisterAGAuthor
    New Member
    May 28, 2010
    Tried that. In fact, I disabled every SMTP option in the appropriate protection profile, and it was still blocking! I ended up rebuilding the protection profile from scratch, and applying the new one. Things are curiously working now. I' m going through every setting to make sure that the two protection profiles are identical.
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