Changes & approvals
Why MX changes always ask you to check by hand
Why does DNSMentor make me verify MX records manually?
Because a mistyped MX target is valid DNS. No rule can derive whether a tenant-specific mail hostname is correct — only the mail provider's own console knows. So every MX write requires a human to confirm the value character by character, and that check cannot be switched off at any skill level.
This is the single most disliked check in DNSMentor and the one we will not remove.
# What goes wrong
Microsoft 365 tenant hostnames follow a pattern derived from the domain, and the pattern is easy to get almost right. A hyphen in the wrong place produces a hostname that does not exist. DNS accepts it, the provider console accepts it, and nothing anywhere reports an error.
# What actually happens next
- Sending servers cannot resolve the target, so they queue rather than bounce.
- They retry for up to five days before giving up.
- Test mail sent from the client's own account arrives fine, because that is outbound.
- The first signal is usually a client mentioning a quiet week.
Copy the value from the mail provider's admin centre and paste it. Do not type it, and do not trust a value from a handover document.
Thanks — noted.
Related
Raise a ticket from inside the platform and your tenant, plan and recent activity come attached automatically. A client currently offline is treated as urgent on every plan.