The worldwide popularity of both personal computers and the Internet has been a mixed blessing. The immediate popularity of the IBM PC was not anticipated. The DOS operating system installed on the original personal computers back in 1982 was never intended for commercial use and therefore was not designed to be secure. In the interest of maintaining compatibility with the early versions of DOS, upgrades to the operating system could not adequately address security issues. As a result, most corporate desktop PCs and notebook computers lack adequate security. Millions of personal computers are used as tools to conduct financial transactions and to store trade secrets, sensitive personal medical data, and employment information. Many of these computers and more are also connected to the Internet to send and receive e-mail and to browse the wealth of information on the World Wide Web. The designers of the Internet never envisioned that it would become the hub of international commerce. As a result, security was not built into the original design of the Internet. The wide acceptance of the personal computer and the Internet has created some concerns for security that are just now being realized. The dramatic increase in computing speeds has added to the dilemma because such speeds aid hackers in breaking into systems. The inherent security problems associated with personal computers, tied to their popularity in the workplace, have fostered new corporate problems. Now internal audits involve the examination of computer records. Criminal investigations and civil investigations routinely involve computer evidence and such inquiries require new methods and tools for investigators and internal auditors alike. That is what this book is all about, and its coming has been long overdue. It deals with practical methods and techniques that have proven to be effective in law enforcement and military circles for years. Only recently has this type of information and tools been available to corporate auditors and investigators.