No Com port visible for Arduino/Genunino Uno

Support
1

Have been using the Uno r3 for a few weeks with no issues. I now have issue uploading a verified skectch with the following error.
Arduino: 1.8.9 (Windows Store 1.8.21.0) (Windows 10), Board: “Arduino/Genuino Uno”

Sketch uses 3258 bytes (10%) of program storage space. Maximum is 32256 bytes.
Global variables use 230 bytes (11%) of dynamic memory, leaving 1818 bytes for local variables. Maximum is 2048 bytes.
avrdude: ser_open(): can’t open device “\.\COM3”: The system cannot find the file specified.

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

This report would have more information with
“Show verbose output during compilation”
option enabled in File -> Preferences.

I purchased a new Uno R3 thinking I had damaged it somehow and have the same issue with the new board.

I also tried out a new Mega 2560 and do not have the issue.

2

Are you sure that the UNO is sitting on COM3, devices will usually get the same number when reconnected but they may also move around. If you run mode in a command prompt it will tell you all attached com devices.

3

Nothing assigned to UNO

Microsoft Windows [Version 10.0.17134.765]
© 2018 Microsoft Corporation. All rights reserved.

C:\Users\aviei>mode

Status for device CON:

Lines:          9001
Columns:        120
Keyboard rate:  31
Keyboard delay: 1
Code page:      437

C:\Users\aviei>

4

Is that with the Arduino Uno plugged in? If so your Uno driver may have corrupted on the systems I would uninstall all the arduino software and reinstall with the newest version.

5

I would try this again with a different USB cord, and connected to different ports.

6

Hi,
Thnks for you replies.

Uninstalled Arduino software and re-installed , now running 1.8.21.0
Tried new usb cable.
CMD mode does not show a com port.
Tried a Mega 2560 with same cables etc and ports are available.

I there a specific driver for the UNO r3 that could be replaced or updated?

7

What does Windows device manager say? Are there any unknown devices shown? What com ports are shown?

8

Hi,

Device manager shows com3 only. No unknown devices.

Regards

Avi

9

Try reinstalling the driver for the com port. Refer to
https://www.arduino.cc/en/Guide/DriverInstallation
and see if that helps.

Also this link may be of use.

10

Hi Avi,

What were you using your Uno for before it stopped working?

11

Hi Stephen,

I was running a nema 14 stepper motor.

Hey everyone, I decided to reload win 10 and have resolved the issue.

Thank you for your support.

Regards

Avi

12

Spending a day reinstalling Windows is not very productive and not much fun. Do you intend reinstalling Windows every time it breaks?

1 Like
13

+1 would be easier to update the driver next time :slight_smile:

1 Like
14

Windows 10 is not so bad I think you can do a fresh install in about an hour, Though you will spend weeks remembering the software and files that you accidentally deleted in the process.