Posted October 18, 20204 yr I use proton mail for my personal email as well as all email related to my site. Nothing sent from IPS (registration emails etc) makes it through to proton mail. I've tested with gmail which is working fine. Is this likely a problem with proton mail, my server's email configuration, or with IPS itself? Given that gmail works I'm tempted to rule out my server config but want to be certain.
October 19, 20204 yr It may very well be your server or the provider. There are configurations such as DKIM and SPF that one provider may need set up which another doesn't, for instance.
October 19, 20204 yr If you are sending using local smtp on your server, check your smtp mta's logs to see what protonmail is sending in response to e-mail requests. If you're using a third-party SMTP service, look into how to see mail logs via your provider. As @bfarber mentioned, you'll want to verify your server isn't on any spam blacklists, and that you have setup correct DKIM/SPF/DMARC records. https://mxtoolbox.com/ is a tool out of many that you can use to validate all that. Start with your logs first.