i did all the right directions i turn off my phone and pres and hold c and connect usb cable but then i get this:

11:19:44| TURN OFF PHONE!
11:19:44| Hold 'C' button on phone and connect phone NOW.
11:19:44| You have 30 seconds...
11:19:44|
11:20:17| Error: Cannot open phone communication port
11:20:19| Disconnected... Unplug the phone

plz help

Don't create double topics

I had this problem the other day as well. My phone was previously recognised but randomly stopped. I couldn't get it to connect. The solution is this : Turn your phone off.Remove and reinsert your battery. Now try to connect. Hope that works.

maybe try to use 2 or 5 instead of C

do as SifJar said, if it still doesnt work try reinstalling the usb drivers.