Just registered to post/ask this. This is not about my store (I don't have one) but about me as a customer of various partners that use Shopify as their store front.
About 3 weeks ago I switched my custom domain from Google to Fastmail. I've been using this domain for 15+ years. Everything is working (meaning I get emails) but I do NOT get any emails from Shopify stores. Talking to Fastmail support they confirm they are not seeing these emails hit their servers.
Remember - I do not have problems getting email - just from Shopify. It's as though my email or domain was blacklisted somehow. I'm not sure where to turn as the partners don't know how to help me (I've reached out to a few of them).
my best guess is that the day I switched providers I ordered something from a store and it's possible the MX server entries weren't done updating to global DNS servers so Shopify tried to send it to my previous hosting provider, couldn't reach it because I had closed my account and then subsequently blacklisted my email from their entire platform as a "non deliverable".
im in the IT biz often mass email providers will blacklist non deliverable email addresses to prevent the system from continuing to try which can reduce the sender's reputation.
im not sure what to do. I don't want to change emails as this is my personal domain but I need to talk/get a hold of someone pretty technical within Shopify to trouble shoot this.
finally this isn't a spam/blocked thing on my end. For example - I got the registration confirmation email for this discussion forum just fine but that isn't the Shopify store front and I suspect it's different email systems in the backend.
I also have this problem from many stores. The mail provider does not seem to matter because some are google and some are not. No one at stores has any clue how to fix this. I don't get confirmations, I don't get invoices and for some stupid reason we can't change our email addresses on our own. I can't possibly reach out to 100+ stores to change my account.
Replying here in case it bumps the question since no one bothered to reply 2 years ago