locks up after 1st upload

new to this, here's whats happening so far (Arduino Leonardo) windows 10 v.1909

i was able to upload the BareMinimum once. after that i get an error message and cant upload it again. any help appreciated. error message:

Sketch uses 3462 bytes (12%) of program storage space. Maximum is 28672 bytes. Global variables use 149 bytes (5%) of dynamic memory, leaving 2411 bytes for local variables. Maximum is 2560 bytes. processing.app.debug.RunnerException at cc.arduino.packages.uploaders.SerialUploader.uploadUsingPreferences(SerialUploader.java:152) at cc.arduino.UploaderUtils.upload(UploaderUtils.java:77) at processing.app.SketchController.upload(SketchController.java:732) at processing.app.SketchController.exportApplet(SketchController.java:703) at processing.app.Editor$UploadHandler.run(Editor.java:2047) at java.lang.Thread.run(Thread.java:748) Caused by: processing.app.SerialException: Error touching serial port 'COM4'. at processing.app.Serial.touchForCDCReset(Serial.java:107) at cc.arduino.packages.uploaders.SerialUploader.uploadUsingPreferences(SerialUploader.java:136) ... 5 more Caused by: jssc.SerialPortException: Port name - COM4; Method name - openPort(); Exception type - Port busy. at jssc.SerialPort.openPort(SerialPort.java:164) at processing.app.Serial.touchForCDCReset(Serial.java:101) ... 6 more

It seems that the Arduino port is busy. Please make sure that the problem isn’t in your PC, by uploading a sketch to other Arduinos, and check that if they work or not. Uninstall and Reinstall all the drivers of Arduino and try the sketch. Also check that if any other software isn’t using the port and make sure that the port is free.


You can try pressing reset on the Arduino and keeping it pressed. When you do an upload, release the reset when the IDE reports the memory usage.

Thanks for the replies. Multiple resets didn’t do much. Tried another board and it did pretty much the same... accepting the first sketch and then back to the original issue.

Indeed it was the port issue being used by other software, in my case either NZXTCam or the Nvidia GeForce Experience or both. Closing all non essential applications worked

Thanks again Monstav

Please see this post Then ensure you are or were not affected.