Does your Office 365 DNS records check fail?

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Recently I was working on building an hybrid Exchange 2013 environment. During the setup for specific mail domains, Office 365 didn’t seem to see the DNS records required. In this case it was the SPF record, that would not be accepted.

However the record was made as specified as requested, TTL was an hour and after several hours it still didn’t pass the check. Other records made at the same time, were checked okay. Unfortunately that delayed other required changes…

Checking somewhat closer I found the culprit: the actual TXT value was:

v=spf1 include:Spf.protection.outlook.com –all

Do you see it? Yes, it seems the Office 365 DNS record check is case sensitive… I don’t know how it became a capital S, but in any case: when they mean exactly, they mean EXACTLY…

Correcting this “typo” resolved the issue quickly and I could continue with other changes. So if your DNS records check fails, check the case!

Sidenote: This also means you cannot have any deviations in your SPF record, when this check is performed. Take that into consideration, it can impact your specific mail flow design or other services that should be allowed to mail.