So you have outsourced most of the services to at least 3 companies (email via google mail servers, DNS via dnsmadeeasy.com, and notification mails via sendgrid.com). So, now the error seems to lie at sendgrid.com and their mail servers and their DNS servers. You of course surely can do such outsourcings to save work and save personnel, but the drawback is of course: you no longer have full control over the processes. If I were to operate such a similar big site like ET, I think I would attempt to do everything in-house, but that's maybe the poor me Ok, thank you for your help. I now know the reason for the bug and how to overcome it. I think we now can close this ticket, at least from my side. Thx again & cu in other, more pleasant threads here @ ET BTW, my public apologies to google for the wrong suspicion/accusation... :-(
No worries. Glad you figured out a solution. I hosted everything myself back in previous years but after things got bigger than a few servers, the system/security maintenance was just non-stop and was wearing me out, which was why I started outsourcing everything.