CypherGuard for Windows A proven stand-alone messaging application with Mercury Primes signature encryption, presence management, chat and file transfer are included to enable a wide variety of business communications. Cost: $24 Buy full version       Trial version       Publisher: CypherGuard, Inc.     Descriptions CypherGuard for Windows: A proven stand-alone messaging application with Mercury Primes signature encryption, presence management, chat and file transfer are included to enable a wide variety of business communications.