No errors.
One or more duplicate ARC-Authentication-Results headers exist.
One or more duplicate ARC-Message-Signature headers exist.
One or more duplicate ARC-Seal headers exist.
One or more ARC-Authentication-Results headers are missing.
One or more ARC-Message-Signature headers are missing.
One or more ARC-Seal headers are missing.
One or more ARC-Authentication-Results headers could not be parsed.
One or more ARC-Message-Signature headers could not be parsed.
One or more ARC-Seal headers could not be parsed.
One or more ARC-Seal headers have an invalid cv value.
One or more ARC-Seal headers are missing a cv value.
Validation failed for the most recent ARC-Message-Signature header.
Validation failed for one or more of the ARC-Seal headers.
An enumeration of possible ARC validation errors (bit flags).