Airplane WiFi Captive Portal on MacOS

There is no spoon. And there is no captive portal.

I recently tested Gogo Wi-Fi on a United Flight with two Macs; one with Sophos Central (Intel Mac) and another without (M1) Mac. In neither case did a "captive portal" pop up. (Even on good days, captive portals are flakey.)

Gogo in-flight Wi-Fi does connect (look at Network Preferences > Wi-Fi), and does allow the airline's own website to load. Once there, you can search for in-flight Wi-Fi documentation and tips. You can completely bypass the need for a captive portal if you go to the airline's Wi-Fi page, then either sign in or sign up for Wi-Fi there. Example pages for a few airlines, all using Gogo:

• unitedwifi.com
• deltawifi.com
• aainflight.com 

Are you able to reach the captive portal if you enter the following URL? 
- captive.apple.com/hotspot-detect.html

That was tried as well and did not work, except when booted into safe mode on the Mac.  After confirming it worked it safe mode, the device was rebooted and the captive page would not come up using any of the methods that typically cause it to come up including the captive.apple.com/hotspot-detect.html page.

I certainly appreciate that captive portals are flaky, but this has been a persistent issue over the past several weeks on multiple flights.  I am used to normal flakiness and this isn't it.  When booting into safe mode, the captive portal comes up as normal.  When booting into regular mode, it no longer comes up despite normal methods that have typically worked.

There would be more than Sophos that would launch in normal mode and not in safe mode (Zoom client, etc.), but those are much easier to shut down than is Sophos.  That is why I am focusing on Sophos as a question for the community to see if others have had recent blocking happen either due to a MacOS update change, Sophos client change, etc.

Note that this hasn't been an issue over the same period for hotel chain WiFi including Hilton, Marriott, Hyatt and IHG.

Keeping the discussion focused on airplane Wi-Fi in the original question, I don't understand why getting a captive portal is so important, when Gogo offers an alternate (and easier) method which does not need a captive portal. My M1 Mac without Sophos Central behaved exactly the same way as my Mac with Sophos Central. In every case, though I did not see a captive portal, I was able to join the Wi-Fi, then pay for it.

It's hard to find a clear answer, though it's entirely possible that airlines are replacing what we think of as captive portals with web pages offering multiple services (inc. entertainment) or auto-forwarding to these web pages. (See attached screenshot of unitedwifi.com)

I can confirm that issue, it is not related to the WiFi itself I guess.

3 weeks ago, I setup a WiFi for a small remote location in Central with Hotspot Type Voucher.

The login page will show on Windows and android devices but none of the MacBooks was able to load the "log into network" website that is hosted on Central. The MacBooks had Sophos EP installed.

We gave that up, kept the SSID in Central but disabled Hotspot in Central and configured the hotspot function on the local XGS Firewall.

The SSID had bridge to VLAN setting, so the XGS was able to handle the clients in the VLAN with it's own voucher hotspot.

All deviced could then load the login website.

I had neither time or felt in the mood to debug that. Eventually it is related to something like automatic Secure DNS enabled by the MacBooks.

We have two users traveling internationally who have both been unable to utilize open wifi captive portal internet connections (United airlines and their hotel). Both are on MacOS 12.4, Sophos EP Agent version 10.3.7. One user did not have the problem before upgrading to Monterey. A third user on the same trip with a similarly configured laptop, but without Sophos EP, has not had the same problem. Frustrating to have them struggling and to come here and see this issue unresolved for over 3 weeks.

The following article has been published in relation to this issue. 
- Unable to connect to Public Wi-Fi networks on macOs Monterey (12)

Some workaround options are available, however, a permanent fix will need to be released by Apple. 

We tried the workaround solutions. None of them works. But when the user reboot Mac into SafeMode, it is able to connect Internet.

it may be related to secure DNS used by macOS