Hello,
I have a client where actionable messages are not working in outlook 2016 or web mail for the o365 users. You get the approval email, but seems like actionable messages are blocked. It works fine on my tenancy and other clients but not on his.
I think I know the issue, seems to be the barracuda spam filter. My question is what needs to be white listed in this case? Microsoft.com? or would maccount@mmicrsoft.com work? or maybe something else?
this is the main issue I believe, the following shows up in the mail properties "Authentication-Results: spf=fail (sender IP is <barracuda IP>)
smtp.mailfrom=microsoft.com"
Thanks,
Robby