Can't open serial monitor

[mattismyo]

I can flash my esp32, but i can't upen (make monitor) the serial monitor anymore.

Traceback (most recent call last):
File "D:/msys32/mingw32/lib/python2.7/threading.py", line 801, in __bootstrap_inner
self.run()
File "D:/msys32/mingw32/lib/python2.7/threading.py", line 754, in run
self.__target(*self.__args, **self.__kwargs)
File "D:/msys32/home/mattismyo/esp/esp-idf/tools/idf_monitor.py", line 116, in _run_outer
self.run()
File "D:/msys32/home/mattismyo/esp/esp-idf/tools/idf_monitor.py", line 192, in run
data = self.serial.read(self.serial.in_waiting or 1)
File "D:/msys32/mingw32/lib/python2.7/site-packages/serial/serialwin32.py", line 273, in read
raise SerialException("ClearCommError failed ({!r})".format(ctypes.WinError()))
SerialException: ClearCommError failed (WindowsError(995, 'The I / O operation has been aborted because of either a thread exit or an application request'))

Anyone know this issue? The com port (COM3) is correct. And it worked the last months without problems.

I tried it with some leds and a sd card. THe program works: The leds are blinking and its writing on the sd card. But still issues with the serial monitor.