Techniques and systems for authentication with an untrusted root between a client and a server are disclosed. In some aspects, a client may connect to a server. The server and client may initiate a secure connection by exchanging certificates. The server may accept a client certificate having an untrusted root that does not chain up to a root certificate verifiable to the server certificate authority. In further aspects, the server may enable the client to associate an untrusted certificate with an existing account associated with the server. The client certificate may be hardware based or generated in software, and may be issued to the client independent of interactions with the server.