SPF_MX_LIMIT_EXCEEDED
error
An mx mechanism in this domain's SPF record expands to more names than receivers will follow.
Something is wrong and mail or certificates are affected.
How we know
spf.test
The ten-lookup and two-void limits of RFC 7208 4.6.4 are spent across a whole include: tree, so neither is visible in any single record. Each name here is sized to land one term either side of a boundary, which is the only way an off-by-one in the accounting shows up as a failure rather than as a plausible number. The address-matching names carry both an A and a AAAA so that `a` can be shown following the client's family, and a /24 so that a matcher ignoring the prefix is caught. The macro names resolve only for one specific sender, which is what makes an expansion bug visible rather than merely different.