The present invention provides systems and methods for allowing an Email User to create a Public Key Infrastructure (PKI) Email Account and thereafter to digitally sign, send, verify and receive PKI encrypted emails over a computer network, such as the Internet. The systems and methods preferably include a Web-based Email System and a Certificate Authority that coordinate their actions to make the process of creating, maintaining and using the PKI Account as easy as possible for the Email User. In a preferred embodiment, a Keystore System may also be used to enhance the management and use of digital keypairs.