Arduino not recognised by the computer W10

I purchased my ARDUINO UNO R3 and used it for a while. It worked flawlessly. Today, when I plug it in it just doesn't get recognized by my pc (Windows 10 x64). I have tried literally everything: reinstall drivers, change the ATMega328p-U chip, clicking the Reset button, changing the cables but NOTHING worked for me!!! It won't be recognized by my computer! please help me to connect the arduino board with pc(lenovo x230,windows-10 x64bit)

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