recently I started using my arduino again, but it can no longer run sketches or anything. All I get is this error:
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
I tried restarting pc, using different port, stopping other devices in device manager from using the port, reinstalling the IDE, and more.
nothing works.
It cant even run blink without throwing this error.
I am using windows 10 pc, Arduino MKR WIFI 1010 , with a usb 3.0 cable, the Arduino used to work too.
none of the other answers on the internet has worked for me.
could this be a problem? -> 
EDIT: I figured out what was wrong. the cable I was connecting to my arduino and computer was ONLY a charging cable, it had no ability to send serial data across to the arduino
