You may have noticed a change in the behavior of the Safe Senders list within Outlook starting in Exchange 2010. Users can no longer add accepted domains to Outlook’s Safe Senders list. Figu...
Updated Jul 01, 2019
Version 2.0
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I certainly understand that you don’t advise turning off the Outlook checks, but by the statement about adding addresses to our hubs you make it clear that you do not understand or have considered real world scenarios many of us are facing. (or apparently any Office365 user for that matter.) Ultimately, your reticence to allow the less perfect preference of not using IPs for delivery assurance will lead us to a world were either much of our email will end up in junk folders, we will have to safe list *.*.*.*, or our users will flee for Google Apps who doesn’t have this tenant of faith.
The truth is sometimes a bit of SPAM is preferable to the dropping of important emails.
PS. Your stance seems to completely disrespect our published SPF of ?ALL. If you were respecting it you would treat any IPs as neutral. Why don’t you follow SPF when it exists?