RP2040 Fails to connect even after REC reset

I've had the RP2040 for a week and initially it was OK and the Arduino IDE worked well, then started to experience download issues and the way to resolve this was pressing the reset button twice, this became more regular. Today the RP2040 is not showing as connected in both the Arduino IDE & system report (Mac User) it's as if the USB port has failed.

So after reading the posts I've attempted the REC reset and strangely the RP2040 appears as removable disk and I can see the two files.

Any suggestions, is my device faulty, if it is is there a process for returning faulty items?

The tricky thing about the boards with native USB functionality like your board is that the USB code that creates the CDC serial port is running on the same microcontroller as your sketch. This means your sketch code can break the USB code, or stop it from running.

This result is unexpected for people who are used to using boards like the Uno, Mega, or classic Nano that have a dedicated USB chip. On those boards, no matter how badly broken your sketch is, you will always be able to upload a new one.

So my recommendation is to try uploading a simple sketch like File > Examples > 01.Basics > BareMinimum and then see if you still have the same unreliability. If you find that the unreliability only occurs when using the real sketch you're working on, that will be an indication that something in your sketch code is interfering with the USB.

Thanks for your suggestion and I now have a fully working RP2040 again!

You're welcome. I'm glad to hear it's working now. Enjoy!