I’ve tried contacting the smartthings support in Australia but we don’t have one so I just get forwarded to the normal support and they tell me to take it to a third party and get charged even though its a software issue.
I’ve also tried factory resetting the vacuum cleaner.
The normal samsung support people dont know anything and just tell me to take it to a repair shop even though its an issue with my smartthings account.
I’ve finally been passed to ST Support
Another thing that might help some people; what fixed it for me was disabling LDPC (an error checking mode for wifi).
I had a Google nest wifi router and the connection was ok, I switched to an OpenWRT router and suddenly it wasn’t connecting anymore.
Then I found this thread https://github.com/kaloz/mwlwifi/issues/278 where they say that ESP8266 or embedded devices are unable to connect to 2.4Ghz. ESP chips are very popular in embedded devices and mwlwifi is a very popular driver for Marvell 88W8x64 wifi routers like Linksys WRT.
The fix was adding the line option ldpc '0' in /etc/config/wireless
config wifi-device 'radio1'
option ldpc '0'
option type 'mac80211'
I hope it helps someone
Been on calls and Emails with Smart Things support and they still haven’t fixed the issue.
I left my network open, I did the registration without security, and then I updated the refrigerator firmware and then change the security back in my network, updated the WIFI setting in the refrigerator and now all is working.
As another commenter mentioned here, the problem for me was Pi-hole for DNS resolution, where outbound traffic from my Samsung device via default UDP port 53 was being redirected by my pfSense firewall via a Pi-hole DNS forwarding resolver. As soon as I temporarily allowed the Samsung device to connect directly to the public internet for UDP port 53 (the default for DNS requests) my Samsung device then registered fine. So nothing to do with the 2.4Ghz or 5GHz Wi-Fi security settings or channel numbers or anything like that for me. Unsure why Samsung devices can’t play nicely with Pi-hole? Perhaps the way it talks to the Samsung defined (DNS?) servers is not the same as the ones Pi-hole uses (being Cloudflare in my config). I’ve heard similar problems with Google Chromecast devices forcing DNS traffic via the Google servers using hard-coded 8.8.8.8 and 8.8.4.4 IP addresses.
+1 for this - I had exactly the same issue. Thanks for mentioning this.
I found the best solution to the Problem. Just get a refund and don’t buy robot vacuums from Samsung. I suspect one of Samsung’s Firmware Updates bricked my Jet Bot AI +.
Anyway I ended up getting a refund from the local shop because Samsung wouldn’t give me one. but I’ve leaned a valuable lesson.
I was getting an error code, 15-200, during the registration process,
of my new Samsung TV.
The solution that worked for me was to turn of IPv6 in my Router.
This also fixed the problem with CAPTCHA checks from google all the time.
Most of my equipment works with IPv6, but not under registration processes .
Sign in with Google during device registration process instead of username and password fixed it for me. Crazy I know…I wish I would have remembered that from the last time I went through this. I’m a Software Developer (not for Samsung though) and I can’t imagine developing software so bad and unreliable. It takes pretty great software developers to make great software that just works…and it takes an army of them…and then they all have to agree…not likely in most companies.
The issue is dns and bad programming 
solution: Change on the device , where you use the smartthings app to configure the connection, the dns settings to “hardcoded” 8.8.8.8. And then start again.
Tried it many time (manual or auto connected) without result. Wifi connection was ok, but the registration in the smartthings environment (last of the three dot in the progress failed after a few minutes and every time . In this thread i saw discussion about tthe dns . Dns was internally passed to my internal router. Changing the dns on my “ configure device” solved the issue . After fulfilling the second 2 progress dots , it fills directly the last dot and everything was ok.
Happy me: but i hope samsung will solve the issue so also non technical persons haven’t a problem
Hi!
I dont understand much Wi-fi and router settings stuff, so i just done some change carefully.
I had the same issue. WAP2, name change, password change didnt work. But I changed them and left them like that (without special characters) just in case. When I started to connect to the machine (in my case JetBot), I went to the wi-fi settings to check the MAC address of my vacuum. Then in the router settings I turned off band sterring, then went to DHCP settings and I added the JetBot to a reserved address. I just come up with a random IP. I use Hungarian Telekom router a F@st 5670 and it has PPPoePassstrough i disabled it. I give the 2,4ghz a fix channel. And turn on WPS (i havent use it tho). LAN IPv6 address autoconfigartion on. I dont know if any of these help you guys, but it seems somehow the router is the problem, not the smart device or the servers. The hungarian samsung techsupport told me to call my local internet provider and ask them for help. 
I hope this helps
If dhcp not 192.168.1.xx Try to set dhcp 192.168.1.xx is work for me
Wow…that was painful…
Tried all day trying to connect my Range to SmartThings and nothing worked. Kept getting the 15-200 error. Message on my range claimed network error. Tried killing power to the range, reinstalling ST app, router reset, phone restart, even deleted my Samsung account. Nothing worked.
I gave up frustrated. Woke up the next morning, this time i decided to connect my Frame TV instead. No issues, connected right away.
Few minutes later, an automated alert on my phone asked if i wanted to connect my Range also. Yes! Hell yes! Been trying to do that for hours the day prior!
The automatic detection connected my Range successfully. Crazy how trying to connect yourself leads absoultely no where until it decides to connect on its own…
