My work wifi runs netgear routers via a lan. when I try to connect with my Samsung galaxy s5 I am asked to sign in but these are open routers no security. When I try to sign in I am redirected to google home page. Connection only stays active for a short period of time then drops the connection. Everyone with a Samsung device is having the same problem but iPhones are ok. I have no problems with my home wifi. This started after the latest android update.
WiFi "sign in" now includes dealing with landing pages asking you to accept terms & conditions. I've noticed more and more public routers throwing these out, and then terminating connections if you don't hit the right web page quickly enough. I've seen iOS and Android respond differently to these things, depending on when the device finds the connection, how tolerant the router is, and so forth.
The solution I've found that works for me on any device is to shut off WiFi, give it a few seconds to "calm down," then start it up again and watch your notifications. If you get a "Sign in to ..." notification, tap on it as quickly as possible. If you don't, and you know it's an access point that exhibits this behavior (like at your place of work), tap the browser icon to open it up, then go to some page that's likely not cached (like SE here), or force a refresh. You should get to the sign-in landing page. Accept, and you should be good at least until your phone goes to sleep (which, sometimes, will cause a disconnect and make the access point whine at you to sign in again).
Yep, it stinks, but the issue seems to be on the access points, not Android.