After updating to 2.3.7.141 on my C7 none of my zigbee devices are working.
Zigbee details under settings shows that zigbee is enabled but all Network State fields are blank (status, pan id, extended pan id). Channel is blank. When i try to scan channels, just get spinning wheel.
Tried rebooting to no avail.
Please help
Have you tried a power cycle?
Instead of reboot:
Shut down hub
Pull power
Wait 1m
Restore power
Removing power resets/clears the radio.
REport after doing that.
Disable, then re enable Zigbee.
Sounds related to this issue :
Yup, you're right...Shut down/restart hub might fix it, but seems like the Radio Disable/Re-enable is pretty sure fix.
Thanks all for the quick reply. Yep, ended up powering down and unplugging the hub for a minute. Everything backup.
Thanks again!
Glad you're up again. 
FWIW, that (the shut-down/power pull/wait/power restore dance) is often the first recommended TS step when you are having issues affecting your Z-Wave or Zigbee radios...never hurts, often helps.
Good to know. Thanks! Just never happened before and got a little nervous.
Thanks to all that rushed to help!
There's a new update?
tried all that - to no avail, downgrade to 140 fixed it, 141 is flawed (at least on C-7)... may be poor QA during holidays...
Doubtful...HE team is consistently careful w/their releases. Of course humans are involved so issues can arise. .141 is running fine on my C7 and we don't have a bunch of these reports coming in so it looks like a very sporadic issue at this point.
Just to confirm, you tried disabling and then re-enabling the Zigbee radio, as well as the shut down the hub/pull power/wait 1m/restore power steps, and neither helped?
If so, it could help if you send your hub ID to @gopher.ny so he can check your engineering logs when he has time.
did full shut down with power off for some time... zigbee did come back up, but as soon as I restored back to 140 zigbee came back up... something amiss in the 141... I have only zigbee devices, may be if you have mix of zigbee/zwave or some other configuration that is not impacted...
hub id sent...
Just to confirm, you didn't try this on .141?
Seems like there is a typo above... Can you review and correct? You meant "...didn't come back up..."?
Either disabling and re-enabling Zigbee or rebooting should fix this in the short term.
Looking at the logs to create a fix for this scenario, next build...
FYI I saw some reports of this on facebook where a reboot and shut down did not bring it back. They did not try the radio off/on trick before rolling back. They rolled back to 140 and it fixed it. So not sure if that was a coincidence or if something broke worse in 141 than the prior issue.
2.3.7.142 is out with the likely fix.
I was about to add that this happened to me when I updated to 2.3.7.141... I found Zigbee disabled and no devices. I enabled it and then rebooted the hub... and only then did I realize I was looking at my "net" hub, which has only network integrations and no local devices. Duh!!
In fact my main hub with Zigbee devices is working just fine on 141.
Here is rule to sense it so i dont forget on future updates and leave zigbee in a hosed state.
Unfortunately i dont see any options or custom methods to disable and reenaable zigbee so rule could fix it by itself.
You could try this (lifted it from @thebearmay 's driver code mentioned here 2.3.7 upgrade... hub zigbee state screwed up after - #30 by thebearmay)
Download the Hubitat app
