Short description of USB Blocker 1.0.02: The freeware NetWrix USB Blocker centrally disables USB devices to prevent unauthorized use of removable media that connects to computer USB ports (memory sticks, removable disks, iPods, etc). USB port access control is a very important aspect of your endpoint security, no matter how good your antivirus and firewall are. The USB device lockdown protects your network against malware and prevents theft of sensitive data. Works without agents!