I am having yet the same problem a lot of people on this forum have or had. I am using an elegoo Uno R3 that i bought recently from amazon. I have been using the board for a couple days and everything seemed fine, where i was able to upload to the board from the arduino IDE just fine. I played with the blink program and everything worked fine, until yesterday. Now i am confused where I could have gone wrong. I was playing with some LED lights and i plugged my Elegoo board into an AC/DC adapter, which i now realize, the adapter outputs 12V, which could have possibly fried some thing on the board, however the lights on the board work fine, and i was able to upload one final RGB LED program before the board became unresponsive to my Windows 10 PC. So here are my problems now:
-Windows 10 states that last USB device connected Malfunctioned and windows does not recognize it.
- I receive the message 'avrdude: stk500_getsync() attempt # of 10: not in sync: resp=0x69'
- i checked device manager and it states 'Unknown USB Device (Device Descriptor Request Failed)', driver does not need an update either.
- I tried uninstalling the USB device then unplugging the board, holding the reset button, then reconnecting the board and releasing the reset button.
- In arduino IDE, board is selected as Arduino Uno and Port is COM1
- I have tried connecting arduino and uploading blink program from a mac book, still same problem.
So i am not sure whether the board is fried or not, because the lights are on, but unresponsive to my PC. If you need any more information I will be replying quickly.
Thank you to anyone who takes their time to help.