STRANGE-BEHAVIOR..PORT NOT showing at all

plz, i knw there are existing thread on similar problem i enecountered... but nt workin!!

my arduino Uno was working fine....till this morning..when my IDE V1.7.10 was unable to even locate or assign port to my board..i have read and try majority of proposed solution..but all require my system to assign port to arduino..have disabled all component that might be using my system port yet all unsucessfull..when i try to run the arduino_debug.exe from my arduino installation file(empty sketch for debugging)..this is what i observed :
avrdude: ser_open(): can't open device "\.\COM30": The system cannot find the file specified.
i tried other USB CORD other system...nt fruitfull
....plz i have a project defense ..............plz!! assist.........all led was working fine including LED13 and the reset button too

laditech2020:
plz, i knw there are existing thread on similar problem i enecountered... but nt workin!!

my arduino Uno was working fine....till this morning..when my IDE V1.7.10 was unable to even locate or assign port to my board..i have read and try majority of proposed solution..but all require my system to assign port to arduino..have disabled all component that might be using my system port yet all unsucessfull..when i try to run the arduino_debug.exe from my arduino installation file(empty sketch for debugging)..this is what i observed :
avrdude: ser_open(): can't open device "\.\COM30": The system cannot find the file specified.
i tried other USB CORD other system...nt fruitfull
....plz i have a project defense ..............plz!! assist.........all led was working fine including LED13 and the reset button too

V1.7.10 is not an IDE from Arduino.cc. It's the (not-so-good) competitor from Arduino.org.

You either need to visit their forums or uninstall that IDE and install the 'real' one from Arduino.cc.
I'm not sure about the very latest V1.6.11 from Arduino.cc, but V1.6.9 is very stable. Avoid V1.6.10.

This is the Arduino.cc download page:- https://www.arduino.cc/en/Main/Software

The decision is your's.

If you're using the Arduino.org board as well, you're probably still in the wrong place.