Mailer was unable to send mailCould not instantiate mail function. - sporadic

Hi.

I am sporadically getting this error on several modx installations on the same server on different domains. My eform call is as follows:

[!eForm? &formid=`feedbackForm` &tpl=`enquiryform` &report=`enquiry_form_format` &from=`[+email+]` &to=`julian@**********` &subject=`Online Enquiry from ******.com` &vericode=`0`!]

And another similar one with different templates - they both have this issue.

Is this a problem with my server, seeing as it works 90% of the time?

Thanks in advance.

Does it happen when two emails are sent close together? The host may be trying to limit outgoing spam.

There might be a timeout setting (or the possibility of adding one) in eForm or in phpMailer that would help.

If you have installed your own enterprise mailserver for some websites:

Maybe you have not properly registered your daemon mailer.

If you are running on some windows servers, like Small Business Server and similar, you have a specific command in order to add a DNS record, you specify the type as ’MX’ for Mail Exchange.
And I am sure it is the same principle with other Operating Systems.

If it is your use case, that’s why it doesn’t work actually:
Your server can not be authorized to send mail if it is not able to serve as a relay of your domain name. It is restricted to prevent spam...

Check port 53 is open for incoming DNS requests too