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Member #382583

Member Since: November 26, 2012

Country: United States

  • I too am having a problem with this device disappearing from the list of COM ports (Win7 64bit) in the device manager and in the Arduino IDE itself (v1.3). I have had the same exact issue on 2 separate PCs, and 2 separate SparkFun Leonardo’s … REGARDLESS of the code uploaded on the device (yes, even BLINK). The board will work perfectly for a few hours, then at some point it just never stays recognized as a COM port (Serial buffer overflow??). Typically, resetting the Leonardo does nothing (transiently a USB device, never a PORT device). Resetting the Arduino IDE does nothing.

    Workarounds for the desperate: Uploading: Even in this state I can sometimes upload to the board if I do what is described on Arduino’s website and elsewhere: Hold down the reset button until the “Uploading” text appears on the Arduino IDE and then let it go. Do this a few hundred times a day and you may achieve enlightenment.

    Port Recognition 1: If the above fails (or below fails), I have had success doing the following. Symptoms: Arduino IDE fails (even after restarting everything) to recognize the port but the port shows up in Device Manager: 1) Press Leonardo reset. 2) In Arduino IDE, quickly go Tools->Serial Port-> and Select the (Temporary) USB COM# (usually Serial port COM# +1). 3) Then, quickly go back to Tools->Serial Port-> Serial COM# should now be available to select. Yes. This has really worked for me, more times than I can count.

    Port recognition 2 (This will only work for as many USB ports as you have): Above fails and Arduino Leonardo is not showing up in device manager: Try switching to a different USB port (at which point the OS SOMETIMES behaves as though it is a new device and I can re-install the drivers. At this point it then assigns a new COM#.

    Port recognition 3 - Use Linux. Or connect your Leonard to Linux temporarily and then connect back to Win 7.

    Seems likely that there’s a serious bug in the Windows driver/Arduino IDE(v1.3). Does anyone have a true fix to this? I need the device to remain recognized by the computer. Anyways, I bought 4 of these clunkers and I seriously regret it. Stick with UNO if you want a dependable product (and preferably NON-SMD Rev3 at that)… this thing is wasting my time.

  • [moved to reply to Joel_Q]

No public wish lists :(