On 11/22/19 7:12 PM, Wesley Peng wrote: > Hi > > when validating DMARC, it use the envelop address, or use from address > from the header? Thanks > DMARC specifically says that validation is to be based on the From: Header of the message (which is different than how SPF and DKIM work by themselves).
This is what gives DMARC issues with some uses of emails when messages pass through relays which do things that break the message in route to their final destination. The email RFCs say that the From: header is suppose to indicate the author of the message, and the minor modifications along the way done by the relays does not invalidate who the author is, so the From should be retain. Basically, this means that those domains that use DMARC, especially at the higher levels, should not use those types of relays, which makes some sense for the original intent of DMARC. -- Richard Damon
