Error in code for EMF

I found on instructabels website Arduino EMF tutorial, i connect everything like that guy , then i copy and paste his Code.
When the code is compiling everything is fine, but when i try to upload my code i got error

Arduino: 1.5.7 (Mac OS X), Board: "Arduino Uno"

Sketch uses 4,660 bytes (14%) of program storage space. Maximum is 32,256 bytes.
Global variables use 252 bytes (12%) of dynamic memory, leaving 1,796 bytes for local variables. Maximum is 2,048 bytes.

So with code everything is fine but i got this error

avrdude: ser_open(): can't open device "/dev/tty.usbmodemfd121": No such file or directory
ioctl("TIOCMGET"): Inappropriate ioctl for device

This report would have more information with
"Show verbose output during compilation"
enabled in File > Preferences.

Can you upload any of the simple Arduino examples successfully?

What serial ports do you see when you look in Tools/Port ?
Maybe you have the wrong one selected?

...R

In some moments when i reset the code its working then not working then working ,
I try to upload some exmp. and it s fine than i upload the code and it s working its uploding.

But for now nothing is happening on LED display, it is 7 LED display

milorad:
In some moments when i reset the code its working then not working then working ,
I try to upload some exmp. and it s fine than i upload the code and it s working its uploding.

But for now nothing is happening on LED display, it is 7 LED display

I can't relate your reply to the two questions I asked in Reply #1, so let me ask them again

1 Can you upload any of the simple Arduino examples successfully? YES or NO

2 What serial ports do you see when you look in Tools/Port ?

I'm sorry but this sentence makes no sense for me

I try to upload some exmp. and it s fine than i upload the code and it s working its uploding.

...R