After a power failure, Photon can't connect to wifi, flashing blue

[moeburn]

So I found someone else who got stuck at "flashing cyan and blue", here:

Photon flashing cyan with red bursts [SOLVED]

Well the battery in my Weather Shield ran down again. All the lights on the Photon were off. I brought it inside and connected it to my PC via USB. It came up in listening mode. (At least that’s something - the last one just had that steady dim D7 blue light on). I used the Particle app to reconnect it to the net. The app said everything was OK but the Photon started blinking fast cyan alternating with quick bursts of flashing red. After reading a bunch of seemingly related threads, I tri…

I followed the instructions. Downloaded the Particle CLI installer, it installed flawlessly. Or so I thought, apparently it didn't install an OpenSSL, I had to go find one manually, then manually move it to the system32 folder.

But I did that. And then I was finally able to run the command:

C:\Windows\system32>particle keys doctor 21003a000151343530343432
Found DFU device 2b04:d006
Found DFU device 2b04:d006
New Key Created!
I couldn't find the file: 21003a000151343530343432_rsa_new.der
Make sure your device is in DFU mode (blinking yellow), and that your computer i
s online.
Error - I couldn't find the file: 21003a000151343530343432_rsa_new.der

I have no idea what any of this means, it says new key created, but then it can't find the key it just created?!