I have searched near and far on the internet for a solution to this but for some reason I can't resolve the "Serial port 'COM X' already in use. Try quitting any programs that may be using it." problem.
There seems to be no number of google searches that I can do to find an answer to my problem. If I continually unplug,re-plug, enable, disable, reset, etc. It may work just once and then I end up with the same problem over and over again.
I have searched for an answer to this problem all over and every forum thread seems to end the same way... they changed something simple (such as the things I have tried below) and it solved all their problems... end of story.
So far I have:
Deleted all existing and previously existing COM&LPT ports (in use or not in use)
Disabled and Enabled
Changed Ports
Uninstalled and Reinstalled Drivers
Reset the board
Used the Enhanced Release Arduino
And I have tried almost every combination of these things.
I have succeeded a couple of times in uploading a sketch but for some reason it doesn't last.
I just can't find the right thread to help me out. Can anyone tell me what I am missing?
This is a windows problem, not a problem with your arduino.
I am afflicted by this, to an extent which varies from time to time. Try unplugging and plugging the USB cable. Try rebooting the computer. Try shutting and re-opening the arduino IDE, which seems to get confused about which serial ports are available and sometimes refuses to give you the opportunity to select the correct one.
You can use the "device manager" app on the "control panel", to see if there are any other devices claiming to have the serial port.
Thanks for the replies. I have tried unplugging and replugging. I have tried disabling and enabling. And I have tried opening and closing. (for what its worth I have also tried installing and uninstalling). And I have tried every combination.
My Device Manager claims no other things working on these COM ports. The IDE just seems to think that something is using the port when its just the Arduino all along.
A few times I have confused it to the point where it allows an upload- but then when I try to monitor the output in the serial monitor, it AGAIN claims that it is already in use??!!
In any case, I'd like to come up with something reliable, even if it is a combination of unplugs and restarts, at least then I can move on...
not sure if it might have any relation to your problem,but try connected reset to ground with a 100uF capacitor, sometimes it's timing related issues with reset,worth a try?
Sounds like you've checked everything, but are you sure there's no software using that port?
I for example, sometimes monitor my serial output with PuTTY rather than the IDE monitor. Then I forget to close it before a compile / upload, so the IDE gives me your exact message. (One advantage of using the IDE monitor of course: it closes when you hit compile.... )
Unfortunately there was not a good answer. I have not been able to upload another sketch using Windows 7 and my Uno.
I ran the port monitor software, only to get shut out by a 'port already open' message. No other ports were available, as I deleted all existing ports in my troubleshooting.
I am going to try for a hard reset on the Uno to see if I can get it cleared up again. I think some combination of the Uno and my Windows OS just don't want to play nice.
I purchased an Adruino Nano on Amazon and its running like a champ. No issues with uploads and my sketches are running with no issues.
I appreciate the help from the community. Maybe not the best answer but hopefully it saves somebody else a lot of time.
I'll post an update if I get any results from the hard reset.