A system and method provides secure access over public communication lines using encrypted information on a removable, portable storage medium. Information relating to a customer's financial account is encrypted and stored to a disk. When a customer desires to purchase goods and/or services on-line or access his financial account, he inserts the CD into a disk drive of a personal computer. The encrypted information is retrieved from the disk and transmitted, via public communications lines, to a computer maintaining a Web site for providing the requested goods and/or services. The computer then forwards the encrypted information to a secure network. A processor on the secure network processes the customer's request, and denies or approves the transaction based on the received information. The results of such processing are returned to the computer maintaining the Web site for completing or aborting the transaction.