Last night I had some success testing the ESP8266 using some example sketches (Blink, WiFiScan, and HelloServer) and they all worked. Today I tried again and was able to get results from WiFiScan (which was still loaded on it). Note that those sketches don't involve connecting any external hardware to the ESP8266…

Then I tried to use the Button example sketch, hoping to use it to get input from my PIR sensor for testing. First, I tried to figure out which pin was pin 2 (the input pin in the sketch) by connecting a jumper wire from the 3.3 V supply pin to each GPIO pin in sequence. This was not a good idea. It caused the USB port to stop working. I got a message saying "The USB port 3 is not working" or something like that (which I didn't realize was a message from Windows) and the COM port stopped showing up in Devices & Printers as well as the Arduino IDE.

Then I tried to troubleshoot the USB cables (because every single post I found about an ESP8266 not working with USB turned out to be the USB cable's fault), with no success. Then I tried plugging the ESP8266 into different USB ports on my computer, which worked, but then I tried the same thing again and broke those USB ports too.

My wireless mouse's battery has failed, so I have to keep it plugged into USB for power. I unplugged it to try that USB port with the ESP8266, so I then plugged my mouse into my USB battery so I could continue to use it. However, it didn't present a large enough load for the battery to stay on, so I plugged my other USB battery (which was nearly empty) into the first USB battery to increase the load so the first one would stay on. That's how I'm using my mouse now.

I haven't been foolish enough to unplug my mouse's receiver and plug the ESP8266 into that port and try probing pins there. I guess I'll have to restart to get my USB ports working again.

But why did connecting the button input GPIO pin to 3.3 V cause the ESP8266 board to draw excessive power (which is what I'm guessing happened) when that's what the button that the sketch is designed for would do? Could it be because it's a sketch designed for Arduino boards?

Update: I restarted my computer and then promptly plugged in the ESP8266 board again without realizing that the jumper was still in place. At least I have two working ports now, not counting the one my mouse receiver is in.