Android Keeps Asking “sign-in to wifi network”

Discussion in 'Know Base' started by securityhope, Nov 10, 2016.

  1. securityhope

    securityhope Administrator Staff Member

    Aug 3, 2016
    Likes Received:
    Trophy Points:
    Q: Why does the message "sign in to WiFi network" appear on my phone when in fact I have connected it to the WiFi router previously?

    A: Those WiFi networks on which you get "Sign in to WiFi network" use captive portal for added protection and use IP based filters to block/allow traffic. Once you log in using your credentials (or 3rd party authentication) on captive portal page, it creates a session for you device. Now, the session timeout for such sessions (after you log in) is configured according to need of that network and can vary from 1 hour to 24 hours. So, once you disconnect from network and come back after the session timeout period, the WiFi router has no information about your device (the session info get flushed after session timeout period). So, it will again ask you to login.

    Q: Android keeps asking “Sign-in to WiFi network” even if WPA/WPA2 is already authenticated

    I'm trying to connect to a DLink Router protected with WPA/WPA2. It's our home router and I can connect perfectly to it from laptops and desktops, Linux and Windows alike. But when I connect to it using my Android phone (XPeria Z), I am always notified to "Sign-in to WiFi Network" after I've entered the WPA/WPA2 password. Tapping into the notification loads a 404 page from my router. Then, from my browser, trying to load any website just keeps looping to this 404 page. Other apps that connect to the internet do report connection problems.

    Being that I'm not on a data plan and always connect via WiFi, I can't install any diagnostic tools unfortunately. FWIW, I've ensured that the connection to my router does not use WiFi Protected Set-up. I've also tried connecting to the router through an old Samsung Galaxy Y, with Android 2.x to same results.

    I wonder if this is a problem with my phones or with my router?

    A: It's a problem with your router. After Android successfully connects to a Wi-Fi network, it tests to see if it can use this network to access the Internet. This is because it's commonplace for Wi-Fi networks to redirect all requests to some kind of login page, until you've logged in. The "Sign-in to Wi-Fi network" notification is nothing to do with authenticating to the network itself: it appears when Android detects that the network is redirecting requests.

    Given that you've said any page brings up this 404 error page from your router, that fits perfectly with the fact you're getting the notification. The fact that the router won't give you pages from the Internet is the root problem: it's nothing to do with WPA or anything like that. Does the 404 page tell you anything helpful?

    Perhaps the router is set up with a list of devices (by MAC address), and the new device isn't on the list so the router won't give it Internet access.

Share This Page