During development with the Spark Cores, I would first claim and flash them at home, to ensure everything worked. Then I’d take them to where I wanted to deploy them, factory reset them ( hold both buttons, release the rightmost button, wait until fast flashing white, release ), reclaim them, and fl…

Factory reset not working

bko August 25, 2015, 4:32pm 2

I suggest you read this thread

In short--Photon has a "safe" mode that is much better than factory reset in my experience.

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