To improve the security of critical government, military, and commercial computer systems, the Department of Homeland Security, desires to eliminate memory resident rootkits. Cybernet Systems Hardware-Assisted System Security Monitor is a Linux-based PC add-on card that can monitor file access and prevent designated sectors from being written, as well as a memory scanner to catch memory-resident rootkits. It does this at a much lower cost and with a smaller logistics footprint than existing technology that currently uses PCMCIA technology. Rootkits are Trojan horses installed by an intruder in order to mask changes made to a system following an attack. They replace or modify intrusion or system-status detecting applications so that these report a properly functioning system to a systems administrator when, in fact, the system has been compromised. Our development of a PC add-on card will provide a GUI tool to allow an administrator to configure the device, which can only be accessed from a USB port. We will also develop a bootable CD-ROM rootkit detection and repair tool for Microsoft Windows.