MS IPv6 fails SPF - need to push user to another server
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Ian Hollaway
1
Reputation point
I have a user whose emails were suddenly being rejected by particular recipients, as they failed DMARC. Issue occurs when using Outlook installed or on the web. Investigation shows that SPF is failing due to the MS IPv6 address not being protected. Our SPF record is set up correctly - there are no issues with emails from other users.
As this appears to be an ongoing issue for MS, I need a way to force this particular user's Outlook to connect to a different MS mailserver, to get away from that 'bad' IPv6. I've tried rebooting the laptop, renewing his home IP, and re-establishing server-connectivity in Outlook - no change. (If it should come up:: asking multiple recipients to white-list the user is not the path I would prefer to travel - yet.)
Any tricks?
Windows for business | Windows Server | User experience | Other
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