I setup a rule to block Domain Spoofing...the rule says to 'block' any email where The 'sender is outside the organization' and the sender domain is my own domain.
For now, I am having the messages sent to me for approval.
This definitely catches some spam, but also caught some valid emails.
Most of them I have been able to whitelist, but I am having problems whitelisting the Shopify new order notifications.
Is there a list of Shopify ip addresses? or someother way? I have already tried to add smtp.shopify.com but that does seem to be working?
(The emails appear to be coming from our own email address)
We are using Exchange365