@feld I’ve had my .ca address rejected. It needs to be a 3 letter tld. And it can’t have a subdomain; addresses at mail.example.com are also frequently rejected. I’ve also encountered three or four websites that whitelist mail providers and claim that everything but Gmail and Microsoft and the other big providers are disposable email addresses and can’t be used.you’ll also have a bad time if your username is a single letter, or contains characters other than letters, numbers, period, and underline.1+@feld.me is a perfectly valid email address. Good luck getting anyone to accept it though.