Problem with Notification e-mails

We have this form set up with a list of recipients that should receive the e-mail whenever a form submission is made. This worked fine for us in previous years so I don’t think the problem is with the setup of our system e-mail. We have Post SMTP installed to handle outbound e-mail from the site.

When a form submission is made, Post SMTP’s E-mail log feature shows the e-mail going out to all the recipients as expected and it says Success. So Post SMTP thinks everything is working fine.

But the problem is none of the recipients actually receive the e-mail. I’m temporarily one of those recipients for testing purposes and I did not get the e-mail. So then I tried sending a Test E-mail using Post SMTP’s feature for doing that. I sent that message to myself and I did receive that one. So the problem seems to be limited to e-mails coming from Contact Form 7 and is not a problem with our Post SMTP setup.

I contacted our ISP because I wanted to see if they had a list of all outbound e-mail messages so I could trace the delivery. But they said they don’t have that capability. I explained everything to them and they suggested we contact you with a ticket. Even though Post SMTP said the e-mails were sent successfully, I don’t have firm evidence that the e-mails actually reached our mail server. If I could see all the outbound e-mails from our server, along with the results of each of those sends, that would be very helpful, but our ISP said they couldn’t provide that. They used to have that functionality in their cPanel on our account, but it is no longer there.

Any assistance you can provide in determining why these e-mails are not reaching their recipients would be appreciated. Thanks in advance.

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