Exchange Online Protection will now evaluate both the P1 and P2 headers in a message against an end users safe and blocked senders list. I know, I’m super excited too! Previously only the P1 header of a message was compared to these lists. Not only...

Update Dec 23, 2014 – I’ve revised this article to make a couple of points clearer. On the mail flow side there are no issues with daisy chaining. However, if the intent is to evaluate the effectiveness of EOP filtering, having a service sit...

I recently worked with a customer who had a configuration in their EOP outbound connector that broke inbound mail for a newly added domain. I want to share this tale in hopes that you not only learn more about EOP partner connectors, but that you decrease...