A method and system for storing to a server a private key that was created on a TCPA-enabled client computer by the user. The user's private key is wrapped in a server non-migratable public key and sent to the server. When the user wants to migrate the user private key to a TCPA-enabled client computer, the user sends a request to the server for the user's private key along with the user's personal migration data for user identification. The server wraps the user's private key in the TCPA-enabled client computer's non-migratable public key, and transmits this "blob" to the client computer, which unwraps the blob to reveal the user's private key.