See this article for how to change wifi config: https://support.smartthings.com/hc/en-us/articles/115002084806-How-to-add-a-SmartThings-Hub-in-the-SmartThings-app (scroll down to “Change a SmartThings Hub’s Wi-Fi network”.)
Why is this a manual process involving powering down the hub and holding in the reset button??? It’s 2019… Are you saying there’s no way to just simply change the Wi-Fi settings through the app still?
Huh, I didn’t actually notice that part. You shouldn’t need to as far as I know. You should only need to hold the “reset” button for a few seconds to re-enable the hub’s setup mode. (Note: this doesn’t actually “reset” anything, it is just how we make sure whoever is trying to change the wifi settings actually has physical access to the hub.)
I’ll ask around to see if I can figure out what’s up with that instruction.
Edit: Nevermind, the hub being offline is a requirement for that menu option to be available in the app. I don’t know why and I don’t have anyone I know who I can ask about that. 
Sorry.
Although I will still say, if your hub is already showing as offline, there’s no need to power cycle it.
I released the pin as soon as the blinking yellow started. I was able to get the hub working but the displayed devices were unreachable and had to be all redone. Smartthings really needs to have a configuration backup feature, not really a professional system until then.
Patrick, why is this option grayed out in the new app. I’ve tried everything but it stays grayed out and not accessible.
Opposite of the standard IT question…
Is it unplugged from power?
Nova5 is right. I do not know why but the Hub has to be in a “disconnected” state for that option to be accessible.
This sounds like a different issue. The hub may need to be replaced.
Hi Al,
I looked at the logs from your hub a bit and recommended a hardware replacement as what we are seeing is that the Wi-Fi driver is failing to initialize the Wi-Fi radio. The errors from the driver are pretty opaque and the system ends up rebooting as, at present, there is a watchdog monitoring processes like the Wi-Fi supplicant (userspace helper for managing Wi-Fi client operations) that eventually try a reboot of the hub as a recovery step.
Here’s a few things I would be interested in having you try:
- Confirm that you are using the provided power supply rated at 5V/2A. If you are, we could try a different 5V power supply with similar current rating. We have seen that in some cases if a power supply is provide insufficient current it can result in internal USB enumeration issues that could cause the Wi-Fi module to not be detected. If you previously used a V2, it’s power supply should also be 5V/2A rated with the same barrel jack connector.
- Try disconnecting power from the hub for several minutes and powering up again. This will ensure that the power rails to the Wi-Fi chip are fully off for a bit (the reboot from the watchdog does not have full control of the power rails to the Wi-Fi chip, just the enable lines).
If neither of those things work hardware replacement (possibly with the failing unit sent to engineering for analysis) is probably our only course of action.
That was just something to try if you had one available and is likely not the problem. Support will probably move forward with replacement. Right now the problem doesn’t appear to be any problem with the Wi-Fi configuration but with detection that parts of the hardware not working properly resulting in reboots that attempt to recover operation.
I talked over this case briefly with @Brad_ST who will drive things on the support side. On the engineering side we agree that this is odd and will be working on root cause analysis. Part of that root cause analysis may include getting RMA’d hardware back from the field for further analysis.
Were you able to try removing power for a period of time to see if this recovers anything? Apologies if you already tried this.
If you continue with customer support via support@smartthings.com or 1800-Samsung, they are best equipped to help. I apologize if I indicated otherwise but there isn’t a backup at this time.
No, there is nothing you can do to prevent the watchdog logic from rebooting the hub as it is part of the firmware. As Brad notes you will need to work with support on hardware replacement.
Regarding standalong Hub v3, I spent 30 min on the phone with tech support and they confirmed there is currently no way to switch wifi networks, through soft reset or other means. The instructions being provided where you’re supposed to go into the app and select add hub and scan QR code, are apparently for the new router/hub combo unit. I’ve tried several times with tech support but the option to change the network is grayed out in the new app.
Is there anyone that can confirm a wifi network change on standalone hub v3 without doing a hard reset?
Yes, link above in psbarrett response.
rtThings-Hub-in-the-SmartThings-app
Read all the way to the bottom of the link supplied above
I can 100% confirm that doesn’t work. I tried 4 times with scanning QR code or entering serial number. Support also went to higher level tech to confirm that there is currently no way to do this unless you have the beta software.
Did you see this note from earlier in this thread?
See post #13 in this thread
Yes, saw that. Still no go. So you all have that option available with a disconnected v3 hub? I’ve tried everything. Like I said, I gave up bc support told me on the phone that this wasn’t possible yet.
I believe the feature was added in December’s app update. Is it possible your app is out of date? Your Hub is definitely in a disconnected state when you are attempting to update the settings?