Fried my Arduino uno

Hi all,
I was wondering if my Arduino could be saved. I fried it recently shorting the board somehow (not sure how exactly) when I was connecting 12V to the Vin pin. result: I saw smoke coming from the M7 diode.
However, when I connect it, the power led, and the orange (pin13?) led are still turning on when I connect the arduino to my computer with the USB-connector. When using the 12V power supply (barrel connector 12V or battery 9V) nothing seems to happen.
Also when I measure the 3.3V pin with my multimeter, while connected to my computer, it reads 5V.
When connected to my computer the computer does not see anything on the USB port.

I also just bought a new arduino and an esp-WROOM-32 and the esp works fine on the same USB-port, but the arduino (chinese cheap stuff I’m affraid) does not seem to have a bootloader installed (but that is not the problem here). So USB port and IDE-software work fine.

So my guess would be that the voltage-regulator and the M7 would be fried. Would you guess I could save my board when replacing those two components?

It sounds like you have fried more than just M7 and the 5V regulator (if that’s the one that you’re referring to).

In my opinion that would indicate that you also fried the 3.3V regulator.

This would indicate in my opinion that the TTL-to-USB converter is also damaged.

Not knowing what exactly happened, the 328P might also be damaged and either is dead as well or it might be dying slowly (meaning it’s unreliable).

Thanks for your quick reply. Might very well be that the damage is larger indeed. Good lesson for me to be more carefull.