Weird problem with win10 and usb to serial port

Just started having a weird issue with the serial port monitoring. If it’s connected to the esp8266 chip thru a standard usb to serial (eg. FTDI232) and I reboot the chip I get the following in the terminal window and it closes. If I close vscode, disconnect, then reconnect and open arduino and open the serial port it’s fine again, then I reopen PIO and the serial port is fine again for awhile.

Traceback (most recent call last):
File “C:\Users\Bill.platformio\python27\Lib\”, line 801, in __bootstrap_inner
File “C:\Users\Bill.platformio\python27\Lib\”, line 754, in run self.__target(*self.__args, **self.__kwargs)
File “c:\users\bill.platformio\penv\lib\site-packages\serial\tools\”, line 445, in reader data = or 1)
File “c:\users\bill.platformio\penv\lib\site-packages\serial\”, line 257, in in_waiting raise SerialException(“ClearCommError failed ({!r})”.format(ctypes.WinError()))
SerialException: ClearCommError failed (WindowsError(5, ‘Access is denied.’))

Any help would be great! When it displays this weirdness the serial port monitor closes/crashes. I can reopen and it works fine until I reboot the device, and then same issue.

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Exact same problem on Adafruit Feather M0. Identical serial output except for last line of output. For me,the last kine of the error message is:
SerialException: ClearCommError failed (WindowsError(22, ‘The device does not recognize the command.’))

The device then crashes and restarts…


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Have now determined that the error occurs when the MCU resets while a connection to the Serial Monitor is active.
Now I just have to find out why my code keeps restarting…

I had the same problem. Did you figure out why the code keeps resetting? I am currently writing a program in which on receive interrupt from the MCU, the MCU gets disconnected and I get the above error. Please help me to solve this issue.

I have the same problem with my Arduino Nano under win11. When I use the reset button of the Nano, it breaks the USB serial link with the same above SerialException.