VB 2010 & Arduino Uno - Serial Communication

Projects Interfacing w/ Software on the Computer
13

Today, I have another problem with Arduino Uno to receive string text.
from VB 2010:
SerialPort1.Open()
SerialPort1.Write("ABC")
SerialPort1.Close()

then upload the attached *.ino file. Then open Arduino serial monitor to track progress.
NOTHING

Please help.
Thanks

VB_ARDUINO_STRTest.ino (588 Bytes)