MicroPython Forum (Archive)

After flashing the newest firmware via dfusedemo, I had some issues with Putty not connecting. Now after some time it shows up in the device manager two times. Connecting to COM4 via Putty gives me this error:

Connection to COM5 works, though. Unfortunately the Pyboard now does not show as a USB device and I can't access the files. Any ideas?

Similar problem from my side.

- blue, green and red leds are always on.
- Windows 10 do not recognize the PyBoard connected to the USB port
- Win10 Device Manager shows: "unknown USB Device (Device descriptor request failed)"
- Dfuse Demo(v3.0.6) doesnt show any available device.

Any hint from your side will be really appreciated.

To rule out a hardware problem boot a Live Ubuntu. It should mount the Pyboard without any drivers on the first try.
After that you know that you‘re facing one of those driver problems windows is famous for and need to install every Pyboard Driver you can get until it finally works!

Thank you for your reply.

using the command "lsusb" in Ubuntu terminal, the pyboard it does not shows.

Any other suggestion?

Thank you in advance for your comments.

Also make sure you're not using a "charge only" USB cable

Yes, switching the USB Cable is a good idea. Sometimes the cables are crap.

I too am having this same problem, have tried all above suggestions and have tried multiple versions for upgrade via DfuSeDemo

I've changed the cable twice and results are the same. Nevertheless, when I start Ubuntu whith Pyboard connected, I found the following message in the Ubuntu start up process:
"usb 5-2 device descriptor read/64 , error -71"

...as expected In Windows 10 also same driver behaviour

I have the very same problem, was working until i tried to update my firmware using DfuDemo software. Everything looked fine over trying to do several versions of Firmware, verified said OK for the down load - but I could not connect, same error as given by others here, USB Port not recognized, error 43.

At one point CTRL-C would get into REPL but that went away.


There was one problem that hung up my system before all of this: I tried to use the Python input function to enter parameters'



Before this I would on occasion have to use chkdsk /f to recover from corrupted files, which worked as advertised then, but not now.

I use on two computers, one running Windows 10 64-bit and one running Windows 7 Professional 64-bit. both same results.

I tried the various Boot types and the 3.3V to X19 method with no luck.

Anymore ideas?

I'm sorry to say that my solution was to buy a new one.