Wednesday, March 20, 2013

iOS 6 on iPhone 5 - Wifi Captive Portal Login Bug

This blog post is my attempt at documenting, as best as I know how, the wifi issue I have experienced since at least iOS 6.0.1 on my iPhone 5. Specifically, the captive portal login process does not work properly. The result varies from network to network. At work there is a free, open wifi network which I am still able to connect to after tapping a button to agree to the terms of service. On the other hand, I am not able to connect to public wifi networks at places like Publix or Panera because their captive portal login page fails to load. That is, it fails to load under the typical use scenario of having both wifi and cellular data turned on. Before I go any further, though, allow me to show exactly what I'm talking about with screenshots.
 
First, with cellular data turned on, this is the captive portal login page that appears when connecting to the open wifi network at work:
 
I tap the big "Accept" button and the process of attaching to the network proceeds. At this point what should happen is that in this same pop-up window a public landing page should load, at which time the blue button at the top-right changes from "Cancel" to "Done". This does not happen, however. My iPhone attempts to load that page, during which time the blue button does change from "Cancel" to "Done" and the data network indicated in the status bar is replaces with the wifi symbol:
Ultimately, though, the public landing page fails to load, as indicated by this error:
 
At this point, though, tapping the blue "Done" button takes me back to the main wifi settings where I can confirm that I have successfully attached to the network (FH):
It takes a little longer to join this network than it used to, but at least it still works. I don't remember where I read it, but I recently remembered reading about someone finding a workaround for not being able to join wifi networks at all: simply turn off cellular data. So, I decided to try this at work. First, I went to Settings->General->Cellular and turned off cellular data:
Then I returned to Settings->Wi-Fi and tapped on the "FH" network. As usual, the captive portal login page slid up from the bottom of the screen:
This time, however, as soon as I tapped "Accept" the public wifi landing page loaded. Also, the blue button at the top-right changed from "Cancel" to "Done":
Upon tapping on "Done" the window slides back down to reveal the wifi settings, showing that I am attached to the "FH" network:
This workaround truly does work, but it's not necessary at work. I am still able to connect to the wifi network even though the public landing page fails to load. What is important is that the captive portal login page does load. As I stated before, though, the captive portal login page does not load for two local businesses' public wifi networks: Publix and Panera. First, let's look at the public network at Publix.
 
I go to Settings->Wi-Fi and tap on the "PUBLIX_CUST…" network, which causes a window to slide up from the bottom of the screen and start loading the captive portal login page (notice the network activity "spinner" in the status bar:
After what seems like an eternity I get an error message stating that the page could not load:
I tap "OK" and am left with a blank, lifeless version of that slide-up window, with no option but to then tap "Cancel":
I tap "Cancel" and the blank window slides back down out of view, revealing the wifi settings which confirm that my attempt to attach to the Publix wifi network has failed:
 
Next I try the workaround that I read about. Again, I go to Settings->General->Cellular and turn off cellular data:
I then return to Settings->Wi-Fi and tap on the "PUBLIX_CUST…" network to attach. Immediately, a window slides up from the bottom of the screen and the captive portal login screen successfully loads:
When I tap the green "Go!" button on the page, the blue "Cancel" button at the top-right of the window changes to "Done" . What is interesting here is that since Publix doesn't have a landing page to load after the login page, iOS is redirected back to the Apple page it was originally trying to load when it was interrupted by the captive portal login page:
At this point I tap the blue "Done" button and the window once again slides down to reveal the wifi settings, showing that I have successfully attached to the "PUBLIX_CUST…" network:


I can then go back to Settings->General->Cellular, turn cellular data on again, and still remain attached to the wifi network:
I have tried this workaround at Panera and had success there, as well, but have not taken any screenshots of the process there. As soon as I can get screenshots there I will update this post.
 

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