Virtual Serial Driver vserial is a sample in winddk 7600.16385.1 The Vserial sample driver is a test tool for serial digitizer drivers. The driver replaces Serial.sys in the driver stack for a serial digitizer. Vserial reads data from a file (instead of the serial port)-Virtual Serial Driver vserial is a sample in winddk 7600.16385.1 The Vserial sample driver is a test tool for serial digitizer drivers. The driver replaces Serial.sys in the driver stack for a serial digitizer. Vserial　reads data from a file (instead of the serial port)