Can't upload to Leonardo: "Port busy"

Hi All

I'm having problems uploading to my Arduino Leonardo.

Has been working for weeks until yesterday, started throwing errors and failing to upload sketches.

I have reinstalled the arduino IDE several times and restarted and unplugged/replugged more times than I can count. Currently running IDE 1.6.8.

The IDE often doesnt show the Leonardo under Tools>Port: in the IDE. I've managed to work around this and attempt to upload the BareMinimum sketch but still wont upload, keep getting this error:
	at cc.arduino.packages.uploaders.SerialUploader.uploadUsingPreferences(
	at cc.arduino.UploaderUtils.upload(
Caused by: Error touching serial port 'COM8'.
	at cc.arduino.packages.uploaders.SerialUploader.uploadUsingPreferences(
	... 6 more
Caused by: jssc.SerialPortException: Port name - COM8; Method name - openPort(); Exception type - Port busy.
	at jssc.SerialPort.openPort(
	... 7 more

Pushing reset button then uploading doesn't fix it either.

I really need this working and i have no idea whats happened, any help would be greatly appreciated.


That’s probably a bug specific to Arduino IDE 1.6.8. Try updating to 1.6.9.

Done that, dont get that output anymore^ the program just hangs on uploading instead

Please do this:

  • File > Preferences > Show verbose output during > upload(check)
  • Sketch > Upload

After the upload fails or freezes copy ALL the text from the black console window at the bottom of the Arduino IDE window and paste it here using code tags(</> button on the toolbar).

Here's the output, the upload has hung for about 5 minutes uploading bareMinimum

Sketch uses 3,624 bytes (12%) of program storage space. Maximum is 28,672 bytes.
Global variables use 148 bytes (5%) of dynamic memory, leaving 2,412 bytes for local variables. Maximum is 2,560 bytes.
Forcing reset using 1200bps open/close on port COM8

Also the Rx LED is on (which hasnt happened before interestingly), Tx is off, L is on

Turned out to be a faulty cable, thanks for the help tho fam