Kwikset z-wave lock inclusion problems - can't seem to get S0 security to work?

one of my kwikset z-wave locks got into a messed up state and i did a factory reset. now i’m faced with needing to re-included it to my z-wave network in home-assistant.

the lock is a model 916 deadbolt. i have aeotec zw090 “gen 5” z-stick with firmware 1.0. (anxious to upgrade to new nabu casa z-stick asap).

i’ve removed the interior part of the lock and located it in close contact with my z-stick. in fact, it is sitting in direct contact with my z-stick.

i’ve been through this process before, but seem to be having difficulty this time. not sure exactly why. i can see that the HA z-wave user experience when adding/deleting devices has changed. mostly for the better from the look of it.

if i try to do an include, the inclusion superficially seems to work however the device shows up as a “generic” z-wave device. it has no visible brand, no model number, etc. and no lock functionality. if i look at the device and expose “Z-Wave Info” tab, it says "Ready: yes. Highest security: None. Z-Wave Plus: No. " all my other kwikset locks (which work ok) have “S0 Security” and Z-Wave Plus “Version 1”. so those values are indicators something is going wrong in the inclusion.

when adding the device, i hit “add device” in HA and a dialog pops up on my screen. there is a link for “security options”. i click it and there is a confusing dialog which seems to have three choices. paraphrasing, the bottom one of them is basically “no security”. the middle one is “legacy security”. the top one is something like “normal security” which says it will attempt to do more modern S2 security and if that fails will fall back to S0 security.

as you would expect, this appears to be a “radio button” interface - i.e an exclusive choice, i.e. you can choose only one option. a strange thing is that no matter which of these three choices i select, when i click on it, the little round selection indicator shows my selection for a second, then turns off (making it appear like nothing is selected). this happens no matter which choice i select. after selecting one option and watching the button turn on, then turn off after a few seconds, i go forward in the process and it would seem i get a confirmation in the dialog that pops up that the option i tried to select is the one that was used (e.g. “legacy security”), so possibly this is just a minor cosmetic issue, but still confusing. still the overall process is failing and i get the feeling that the underlying problem relates to security.

inclusion completes. as i described above the resulting device comes in as a “generic” device, with no security, thus HA fails to see it as a lock, and i seemingly have no choice but to delete/exclude this device and try again. i’ve tried many times. i’ve tried selecting the “legacy security” and the “normal security” options - no difference in the final outcome.

i’ve put brand new batteries in the device.

i’ve heard of some quirks with kwikset using something called “whisper” inclusion and requires that it be very close to the z-stick. thus, as i mentioned, i’m holding the device and the z-stick literally in physical contact with each other, but this doesn’t seem to help.

in between my multiple repeat attempts at inclusion, i’m doing a “delete” from HA and selecting the option to “remove a working device”. this process works smoothly and definitely indicates to me that the device is getting removed from HA and excluded from z-wave each time.

i changed log level to “debug” and restarted Z-Wave JS add-on. this took a while, but (the restart) did not change the behavior i was seeing.

in the logs, i see these maybe-relevant bits:

2025-07-12 16:20:10.700 CNTRLR   [Node 015] Security S0 bootstrapping failed, the node was not granted the S0 s
                                 ecurity class

it looks like an initial handshake takes place, the lock reports on various command-classes it supports, including “security (0x98)”. then soon after, there appears to be more back-and-forth exchange on security, culminating in the above failure message.

anyone have any suggestions of things to try? i’ve somehow done this successfully in the past, but it was a while ago. i’m doing everything i can think of to increase my changes but having no luck.