06356937 is referenced by 335 patents.
A full-featured e-mail system is used in both Internet-based and client-side (personal computer) forms. In each form, either basic e-mail service is provided to system subscribers or a secure, premium service with authentication, concealment, integrity, and non-repudiation functions for electronic messaging services is provided. In either form and at either level of service, subscribers can work off-line on their own computers with proprietary software loaded or, alternatively, on-line on any computer with an Internet connection. The system is interoperable, to preserve security, with all S/MIME compliant software applications, even for those users not subscribing to a service implementing the disclosed system. Digital certificates can be provided as a security service of the disclosed system, rather than requiring a second source with separate verification procedures. As additional optional features, the subscriber can control compression of outgoing attachment files, rather than having that function absent or operate in some automatic way. Decompression of such file attachments when received occurs automatically for subscribers, without having to invoke a different program or system. Interactive help features, book hierarchy uniformity for messages, accounts, certificates, virus warnings, and dual naming capability are also provided and available to subscribers in both the Web-based and the client-side application forms disclosed herein, and in both basic and premium service levels.