" can't open device ~ com4 ~ " messsage means, I thought windows7 driver,
so I tried applied FTDI, CH341, ATMEGA328P DRIVER, CDM, but I can't fix up.
SO, I don't know, How to fix it.
What is the cause?
Uncheck the checkbox next to "Show verbose output during: compilation"
Check the checkbox next to "Show verbose output during: upload
Click "OK"
Sketch > Upload
After the upload fails, you'll see a button on the right side of the orange bar "Copy error messages" (or the icon that looks like two pieces of paper at the top right corner of the black console window in the Arduino Web Editor). Click that button.
In a forum reply here, click on the reply field.
Click the </> button on the forum toolbar. This will add the forum's code tags markup to your reply.
Press "Ctrl + V". This will paste the upload output between the code tags.
Move the cursor outside of the code tags before you add any additional text to your reply.
This report would have more information with
"Show verbose output during compilation"
enabled in File > Preferences.
Arduino: 1.0.6 (Windows 7), Board: "Arduino Uno"
Binary sketch size: 1,082 bytes (of a 32,256 byte maximum)
processing.app.SerialException: Serial port 'COM4' already in use. Try quiting any programs that may be using it.
at processing.app.Serial.<init>(Serial.java:171)
at processing.app.Serial.<init>(Serial.java:77)
at processing.app.debug.Uploader.flushSerialBuffer(Uploader.java:77)
at processing.app.debug.AvrdudeUploader.uploadViaBootloader(AvrdudeUploader.java:175)
at processing.app.debug.AvrdudeUploader.uploadUsingPreferences(AvrdudeUploader.java:67)
at processing.app.Sketch.upload(Sketch.java:1666)
at processing.app.Sketch.exportApplet(Sketch.java:1622)
at processing.app.Sketch.exportApplet(Sketch.java:1594)
at processing.app.Editor$DefaultExportHandler.run(Editor.java:2382)
at java.lang.Thread.run(Thread.java:619)
processing.app.debug.RunnerException: Serial port 'COM4' already in use. Try quiting any programs that may be using it.
at processing.app.debug.Uploader.flushSerialBuffer(Uploader.java:101)
at processing.app.debug.AvrdudeUploader.uploadViaBootloader(AvrdudeUploader.java:175)
at processing.app.debug.AvrdudeUploader.uploadUsingPreferences(AvrdudeUploader.java:67)
at processing.app.Sketch.upload(Sketch.java:1666)
at processing.app.Sketch.exportApplet(Sketch.java:1622)
at processing.app.Sketch.exportApplet(Sketch.java:1594)
at processing.app.Editor$DefaultExportHandler.run(Editor.java:2382)
at java.lang.Thread.run(Thread.java:619)