Hey all,

I got a new router and once again, I had difficulties setting up the smart plugs.  But to my credit, I managed to identify the issue and resolve it.  I'm posting this here because maybe it will help someone else.

Background, I had my ISP bridge my router because it was interfeering with some networking I was atempting to do.  They bridged it Friday, and all my WiFi devices were kicked off the ISPs router WiFi, so I had to configure everything up for the new router.

I have 3 TP-Link HS103 v2s from several years ago.  I tried to set up the one for the living room lamp, and once I went through the process it would just fast blink blue.  I would get an error in the Kasa app telling me to retry the setup.  After factory resetting it several times ( holding the power button for 10 seconds until fast blink orange ), I moved onto the next plug.  The next plug worked fine.  The third plug worked fine.  I was just using this plug on my old ISP provided router on Friday ( it's Monday ).

So I popped onto my new router - which I had flashed with OpenWRT because networking - and I saw 2 things which tipped me off right away what the issue was.  I have a big server ( for 2012 standards ) and it has a static IP of 192.168.1.222.  I noticed that there was a DHCP lease for this IP but it had the same 4 digits at the end of the TP-Link WiFi network the problem plug uses in order to initialize configuring the plug.  I checked the MAC address on the problematic HS103 v2 plug and sure enough it was an exact match.  I changed the OpenWRT DHCP server to only provide addresses between 100 and 199 - it defaults to 100-249 ( starting at 100 and allowing 150 leases ).  I deleted the lease out of the OpenWRT configuration file ( had to SSH in and edit the config file as the UI didn't allow you do manage this file ), then I restarted the DHCP server.  Once I factory reset the plug and went through the setup again, it worked the first time.

I'd have figured either the router or the smart plug would have detected an IP conflict ( same IP being used by multiple MAC addresses ) and kick up a stink.  I'll have to mention this to the good folks over at OpenWRT.

I hope this helps someone.