Blog Post
Strengthening Email Ecosystem: Outlook’s New Requirements for High‐Volume Senders
It is best not to use a forwarding service, or if you still want to, choose one that uses the Sender Rewrite Scheme (http://www.open-spf.org/SRS/). This is the only way to avoid a forwarded email being rejected by Outlook. Also, if the email author's address domain is a high-volume sender, they must sign the email with an aligned DKIM.
Thanks, that is interesting information, but as mentioned I have been using the forwarding (by the same domain host) for over 20 years with no problem. Plus, of course, the first two emails from AXS's sales systems were delivered successfully. Since it seems gmail has no issues with the forwarded email why should I have to take action to resolve what appears to be a Microsoft specific problem?
- CdaryJul 19, 2025Copper Contributor
Microsoft has decided to strengthen its inbound filtering to let less phishing slip through the net. This is fundamentally a good decision for security reasons, but it excludes redirection servers that don't use the Sender Rewriting Scheme. This scheme was already recommended to avoid the risk of SPF laundering. It has now become necessary for secure delivery to the MAGY (Microsoft, Apple, Google, and Yahoo).