What is a TXT record with the form ms=msXXXXXXXX used for?

Question

I've noticed that some domains have a TXT record with the form ms=msXXXXXXXX, where each X is decimal digit.

For example ms=ms97284866

What is this kind of TXT record used for?

Solution 1

They are usually used by automated validation procedures whose purpose is to detect wheter you are the rightful owner of a domain; they will ask you to create a TXT record with a specific text string in the domain DNS zone, and then check if the requested record is actually there; if you were able to create it, it's safe to assume you own (or at least manage) that domain.

A record in the form ms=msXXXXXXXX is typical of the procedure used for domain validation by Microsoft Office 365.

Solution 2

This signifies that the domain is an Office 365 tenant.

Comments

[Brian]

References for it: External Domain Name System records for Office 365 and follow the link for "Gather the information you need to create Office 365 DNS records" to see how the msXXXXXXX txt records are used.

[Massimo]

Well, technically it only signifies it was validated as usable by Office 365 at some point in time, and then someone left the record there (which becomes completely useless after validation is performed). It says nothing about Office 365 actually being in use (as opposed to, f.e., the MX record pointing to Exchange Online).

[spottedmahn]

updated url: External Domain Name System records for Office 365