Arduino serial port COM1 problem

1. Connect your Arduino hardware.Open Arduino IDE.

2. Go to "Tool".

3. Go to "Port".

4. Select the port to which Arduino is connected.(If no other external drive is connected except Arduino,there will be only one port)

   This will tell Arduino IDE the port to which your hardware is connected. After that,you will be able to upload your sketch successfully

If you run Arduino IDE on Ubuntu (Arduino 1.5.7 and Ubuntu 14.04 in my case), most possibly you cannot upload to Arduino board, caused by the error of:

avrdude: ser_open(): can't open device "/dev/ttyUSB0": Permission denied
ioctl("TIOCMGET"): Inappropriate ioctl for device

To fix it, enter the command:

$ sudo usermod -a -G dialout <username>
$ sudo chmod a+rw /dev/ttyUSB0

Where is your user name in Ubuntu, /dev/ttyUSB0 is the detected device of your Arduino board.

First line doing add group (dialout) to username
Second line doing write and read permission to "/dev/ttyUSB0"

I was getting the same error on Ubuntu 14.04 with Arduino Uno. What worked for me was first selecting the appropriate port under Tools > Port and then changing the permission of the port using command like:

sudo chmod a+rw /dev/ttyUSB0

Then the error disappeared and I could upload fine.