The direct answer
A self-generated certificate does not satisfy Gmail’s requirement for an accepted VMC or CMC from a third-party certificate authority. Self-asserted BIMI is a separate, certificate-free approach with different provider support.
Why does a valid-looking certificate file not suffice?
A receiver needs evidence it accepts, not simply a file that a certificate parser can read. Generating your own certificate or embedding your logo in one does not establish the issuer trust and mark validation required by Gmail.
Likewise, installing an ordinary website certificate at the asset host only addresses the HTTPS connection. It does not turn that certificate into a VMC or CMC.
Which route should I investigate?
If Gmail is in scope, confirm the mark-certificate route, your eligibility and issuer acceptance before purchasing. The BIMI Group notes that acceptance is a mailbox-provider decision, so inclusion in an issuer directory is not a universal guarantee.
If you are considering a certificate-free deployment for another provider, check that provider’s own rules. Describe it as self-asserted BIMI, not as a self-signed VMC, so the technical and procurement teams are discussing the same option.
Sources & further reading
Provider guidance checked on . Requirements can change; check the original guidance when implementing. Planning checklists and examples are BIMI World’s editorial suggestions.