Example not uploading

I keep trying to upload a new example in the sketchbook to my decimilla, but it keeps saying at the bottom of the window "serial port... already in use. Try quitting any programs that may be using it.

I quit all the programs I am using and still nothing. The board is linked by a-b usb 2 cable.

I have managed to upload examples before (i.e. blink) and its still blinking but today it decided not to upload.

Anone know why?

What operating system are you on?

Did you ever update a program besides the blinking LED?

Check out the troubleshooting guide for some common suggestions.

v 10.4.11

Yeah I think so it was this time last week so as I remember... I hadn't worked out the code completely and had the wrong value resistor so some examples didn't work But i think I did manage to change the tempo of the LED I think on the blink example.