Connot set Core Wifi Credentials

I am trying to set the wifi credentials for a pre-claimed Core device using the Particle phone application but I am encountering some problems. I have done this before but it has been a while, so maybe things have changed since then.

I set the Core to listening mode and then go to the Particle App and press the “+” button and choose “Setup Core”. However, instead of getting a list of nearby Core wifi signals, I am getting an error message reading:

“We have encountered an error. Please visit for more information. Status code: 401”

I don’t know if this is a temporary thing or maybe it is because I haven’t done this for some time and things have changes since.


I had the exact same issue 2 days ago, trying to get my old Core working again on my new WiFi access points. Give up on the phone app, the best way is to use the Command Line Interface (CLI) and go in via the DFU method. It seems difficult, but once you sit back follow it correctly, it should work fine.

Take a look at my old post, which references several other great posts.

The only thing, the dropbox links no longer work, and ended up using the “particle doctor” suggested from this post.

Good luck!

Thanks. Eventually I managed to do it using the CLI as you suggested.