Also Conrad, I wanted to mention that using Gmail for sending the internet-ID during host install seems problematic. I don't know if they are tightening up security but sending via gmail seems unreliable, even when 'Less secure app access' is enabled, more often than not the email sending is blocked. This always happens when hosts are installed at customer sites (i.e., different IP's) it get blocked but if installing from a know IP (like our office - that has been used before and 'authorized' it) - it works OK.
I see. But unfortunately, there is little we can do in this situation :) We only provide interface to connect to an SMTP server. The actual mail sending process is beyond our control and happens on the mail provider side. In our documentation we use Gmail as an example, but perhaps there are better alternatives.
FYI we have started using mailJet (https://www.mailjet.com) and it works from the installer. It is free for low volume use (200 emails\month) and takes very little config with SPF\DKIM available to ensure less 'spammy' delivery.
Thank you for the suggestion. We will test out this service and will perhaps start recommending it in our documentation.
Let me know if you need further assistance.