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    (bug)SMTP settings not validating hostnames with numbers on it

    Asked by bodinjovanovic on October 08, 2013 at 08:32 AM


    I have problem with adding notification email address for my form. When I fill hostname in our case is smtp.365dana.rs I got error Hostname is not correct!


    Thanks in advanced,



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    JotForm Support

    Answered by guilledutra on October 08, 2013 at 09:17 AM


    I was able to replicate this issue using smtp host names containing numbers in the domain part of the url, 

    I will forward this issue to our second level support team because it seems to be a problem only related with the validation of the smtp hostname.

    As soon as we get news about it, we will let you know, meanwhile you can use a free smtp service like Mandrill



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    Chief Technology Officer

    Answered by eee on October 11, 2013 at 04:05 AM


    According to RFC 952 (that we're using on verification), hostname's can not start with a digit or with a hyphen, and must not end with a hyphen. 

    RFC 1123, changed that rules and I have re-implemented our verification part according to RFC 1123.

    You can use smtp.365dana.rs on your SMTP accounts,

    Kindest Regards,