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Hey
We are investigating the possibilities of using IPv6 in combination with Microsoft Exchange Online and have a few questions about this.
Is it possible to enable IPv6 online in Microsoft Exchange and how do we this?
What is the method to let a Windows client communicate with Microsoft Exchange online via IPv6?
Are there other things to watch out for?
Thanks in advance!
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Does reply below from Andy help? Do you have any other concern?
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If I see your name, you are probably Dutch.
You are probably asking because of the VNG?
https://www.vngrealisatie.nl/producten/ipv6-bij-gemeenten
See my link below (in my answer to AnyDavid), you have to contact MS support and ASK (beg probably) them to open it. They will not understand and reply it's already open and such. This is not true and keep replying it is not open for Inbound anonymous connections (server to server and NOT Outlook or other clients).
I'm talking to support for about two weeks or so and still got nothing to show for. Yet. Hang in there man!
IPV6 is already enabled and supported in Exchange Online
https://learn.microsoft.com/en-us/microsoft-365/enterprise/ipv6-support?view=o365-worldwide#exchange-online-and-ipv6
It is NOT enabled by default.
Maybe it is for client services like Outlook, but anonymous inbound connections are NOT enabled.
You specifically have to ask Microsoft to enable it. Unfortunately, MS support also keeps saying it's enabled even if I can prove it is not...
Also see this article confirming that it's NOT enabled by default: https://learn.microsoft.com/en-us/microsoft-365/security/office-365-security/support-for-anonymous-inbound-email-messages-over-ipv6?view=o365-worldwide
Quote from the link:
"Before your organization can receive anonymous inbound email over IPv6, an admin needs to contact Microsoft support and ask for it."
My proof is here: https://www.internet.nl/mail/kmcsolutions.nl This issue is on most (all?) domains that host their mail in EXO.
This is a Dutch government sanctioned website to check for issues, and IPv6 is one of them on most Exchange Online servers.