I'm an IT administrator for a school corporation using Google Apps for Education. We have restricted delivery to and from our student accounts. Webmaker password resets and other communication emails are being rejected because somewhere in the header there is a domain that's not on our white list. The following are the ones that I can find in the header and have added to our "allow list" with wildcards. *.amazonses.com *.webmaker.org *.nodemailer.com *.cloudflare.com Any guidance or any other domains that I might be missing would be most helpful. Thanks.