In brief
Connected to guest Wi-Fi but no login page appeared. How phones detect a portal, why HTTPS blocks it, what private Wi-Fi addresses do, and the one sentence to tell your guest.
"I'm on the Wi-Fi but nothing opened." Every business that runs guest Wi-Fi hears this. Most of the time neither the box nor the access point (AP) is at fault. The problem is in how the phone notices that a login page exists. This post explains what the phone does, where it gets stuck, and what to tell your guest.
How does a phone notice the login page?
When a phone joins a Wi-Fi network it runs a small test in the background. It sends a simple request to a known address and looks for the answer it expects. Apple devices use their own check address; Android devices use a connectivity check address.
- If the answer comes back as expected, the phone decides "the internet works" and opens nothing.
- If the answer is different (because the box intercepted the request and redirected it to the portal), the phone decides "there is a login page here" and opens a small window. Apple calls this window the Captive Network Assistant; on Android it appears as a notification and a mini browser.
The box performs that redirect. When one link in the chain breaks, the window never opens, or the guest closes it, tries a browser and sees a blank page.
Why doesn't the window open? Five common causes
1. The detection request never reaches the portal
If the list of addresses reachable before login (the walled garden) is wider than it should be, the phone's check request goes straight to the internet. The phone assumes it is online and no portal appears. Keep only what is truly needed in the walled garden: the SMS provider, the link to your privacy notice, and perhaps your own website.
2. The guest opened an HTTPS page first
If the window closes, the guest habitually types a big search engine or social network into the browser. All of those use HTTPS. The box cannot turn an encrypted connection into the portal; if it tried, the browser would show a certificate warning. On sites that use HSTS the browser does not even offer a "continue anyway" option. The guest only sees "secure connection failed". The fix is to type an address that starts with http://. The box catches that request and shows the portal.
3. A private Wi-Fi address makes the device look new
Current iOS and Android versions generate a random hardware address (MAC) for each Wi-Fi network instead of using the real one. Device remembering on the box is tied to that address. Normally the phone keeps the same random address for the same network and remembering works. But when the guest taps "forget this network", or chooses the rotating option on iOS, the box sees a brand new device. The portal opens again. That is not a fault; it is the phone's privacy choice. The guest simply verifies again.
4. The device is already remembered
Some guests expect a portal that never comes, because their device was remembered and the internet is already open. The guest complains that "the page didn't open"; in fact nothing is wrong. Ask them to open any website.
5. The window was closed and the network flagged as "no internet"
If the Apple window is dismissed, iOS sometimes treats the network as having no internet and falls back to mobile data. On Android, choosing "use this network without internet" has a similar effect. The fix is to forget the network and join again.
The one sentence to tell your guest
"Join the Wi-Fi and don't close the window that pops up; if nothing opens, type an address starting with http:// into your browser."
Print it on a small table card or next to the QR code. It solves four out of five cases.
A quick check on the business side
| Symptom | Likely cause | What to do |
|---|---|---|
| No phone shows the portal | Walled garden too wide, or guest DNS bypasses the box | Trim the list; point guest DNS at the box |
| Only iPhones fail | Apple's check address was added to the walled garden | Remove it |
| Portal opens, page hangs after the code | Post-login redirect address is unreachable | Check the redirect address |
| The same guest logs in every day | Private Wi-Fi address rotates, or the remember period is short | Extend the remember period in the plan template; inform the guest |
| Window opens but stays blank | The portal page pulls fonts or images from outside | Keep portal assets on the box |
How the box makes this easier
In Hotspot-Box the portal redirect, the walled garden list and the device remember period are all managed from one panel. Plan templates let you set the remember period by business type: short for a cafe, a whole term for a dormitory. Portal fonts and images live on the box and do not wait for external resources, which lowers the chance of a blank window.
What is different on Android?
Android announces the portal with a notification: "Sign in to network". If the guest ignores it, after a few minutes the phone treats the network as offline and switches to mobile data. The Wi-Fi icon stays visible but no traffic flows through it; the guest says "I'm connected but nothing opens". The fix is to tap the network in Wi-Fi settings and choose the sign-in option.
Then there is the private DNS setting. If "Private DNS" on Android is pinned to a specific server, the phone ignores the network's DNS and tries to reach out over encrypted DNS. Because the portal redirect relies on DNS, the window never opens. Ask the guest to set it to "automatic"; they can switch back after logging in. This case is rare but hard to recognise, since the same phone works fine on other networks.
See the box page for details and the FAQ for common questions. If your setup has a special case, contact us.