Office365 Autodiscover CNAME Record Doesn't Work

[oalvarado]

Hello,

I already have seen your post about this very same error:

Why cant Office 365 find my CName record for autodiscover?

I have added 3 DNS records as instructed by advice at portal.office.com The MX and TXT records verify quickly when I add them However the CName record does not verify I get the message [555555] or host name autodiscover with value autodiscover.outlook.com The record shows at Cloudflare DNS as [777777]

The problem is neither the solution works for me, nor any other way around on CDN services is working:

At this point, I don’t know what to do. Could you help me in some way?

Regards,
O. J.

[oalvarado]

Here the configuration:

[sdayman]

Your records behave as if you have CNAME flattening turned on for subdomains. Is this a Paid Plan (Pro/Business/Enterprise)?

https://support.cloudflare.com/hc/en-us/articles/200169056-Understand-and-configure-CNAME-Flattening

[oalvarado]

Thank you @sdayman

I changed the CNAME Flattening configuration to “Flatten CNAME as root” and it worked. Thank you for your help.