I have been confused why when it seems even the most basic hello sketch that uses serial communication works when uploaded and will work when the reset button is pressed... But if you remove the power and apply power again they sketch will not start... It just seems to sit in a limbo state... Even this basic sketch does it.
Yes I did... even tried using a USB wallwart to power it just to check if the PC was doing some serial handshaking or something that was making the arduino bootloader think there was a sketch being uploaded...
It works fine on my Uno - using Arduino 1.5.6 on Xubuntu 14.04
If you disconnect the USB connection while the serial monitor is open it is possible that when you next connect the Arduino it appears as a different serial port.
Buckaboobob,
sometimes the serial port gets jammed in between sketch uploads.
But for this instance, It may be the serial port speed. I notices it is set at: 115200
Check your Serial Monitor speed (bottom left).
FWIW: you may need to set the speed before open the Monitor.
See it that makes a difference.