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When I first set up my domain on O365, I was told to set up the MX record as "domain0i.mail.eo.outlook.com", which I did and has been working fine ever since, and still does.
I was reviewing things today and happened to look in the Setup DNS settings of my O365 Portal, and it said the MX record was incorrect. It was now expecting "domain0i.mail.protection.outlook.com"
Did Microsoft change the Office 365 MX record address? Why? Is there any documentation on why this change? I've tried searching and can't turn up anything. I don't remember ever receiving any communication telling me that I needed to change my MX record to this new value.
Thank you.
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You will find that Microsoft will make changes without informing the tenant admins. You'll have to be proactive and watch the blogs, roadmap, and I'd recommend joining the techcommunity. Luckily your change didn't have a negative affect on your setup.
I should rephrase. I wasn't really asking IF MS changed the MX record requirement at some point. I KNOW that they DID. The question is more, why was it changed, when, and why did I not ever receive any communication about the change?
When I first signed up for Office 365 three or four years ago, the MX record that Office 365 told me to implement WAS in the format of domain0i.mail.eo.outlook.com. And this even still works today.
NOW, today, Office 365 is telling me that my MX record should be in the format of domain0i.mail.protection.outlook.com. So Microsoft DID change the MX record requirements sometime in the last 3 or 4 years.
Again, why did they change it, when, and why wasn't I notified of needing to make the change in my DNS?
As I said, my domain Office 365 email is still working using the older MX record format, so I'm not really inclined to change it without understanding why I need to.
Thank you again.
(And yes, I'm very familiar with the document you linked to. That merely documents the current requirements. That has no bearing on what the MX record requirements were in the past.)
Hi Cory,
No, Microsoft doesn’t change the MX record of Office 365 service. It should be domain.mail.protection.outlook.com. Please kindly check if your MX record is something like this. Here is an article for your reference: https://support.office.com/en-us/article/Create-DNS-records-at-any-DNS-hosting-provider-for-Office-365-7b7b075d-79f9-4e37-8a9e-fb60c1d95166?ui=en-US&rs=en-US&ad=US#bkmk_add_mx
Regards,
Barry
Hi Cory,
Feel free to contact us if you need any other help.
Regards,
Barry
Hi Gory,
Many thanks for your reply.
The MX record is domain.mail.protection.outlook.com now. If you want to know the updates of Office 365, we recommend that you monitorOffice 365 Roadmap for more information. Your understanding is highly appreciated.
Regards,
Barry