Happ error “Unknown content type”

What happened technically

The app made the request and received a response. Then it tried to work out what the response was — a subscription list, a single configuration, JSON, an encrypted happ://crypto payload — and none of the formats matched. Rather than guess, it stops and says so.

So the failure is about content, not connectivity. Something is at that address; it is the wrong something.

The usual culprit

Providers give you two addresses that live in the same place and look alike:

• the dashboard — a page you open in a browser to see your account;
• the subscription — an address meant for the app to fetch.

Copying the dashboard address out of the browser’s address bar is easy to do and produces this error every time, because what comes back is a web page.

The fix is to find the control that explicitly offers the subscription or import link and use its copy button.

The browser test, done properly

The widespread advice — open the link in a browser, and if you see a normal page you copied the wrong thing — is not reliable, and following it will send some people looking for an address that does not exist.

Subscription servers commonly serve different things to different callers: a readable page to a browser, configuration data to the app. A normal-looking page is therefore the expected result for a correct link.

What the browser actually distinguishes is narrower:

• a login form — you have the dashboard address, this is the real signal;
• a page from your service showing your subscription — normal, keep the link;
• a file download or a wall of text — normal;
• an error code — inconclusive; retry before concluding anything.

When the address is right and it still fails

Services change things. Authentication can be switched on, a subscription path can move, a server can start returning an error page. All of these produce this message with an address that was correct yesterday.

Open your provider’s dashboard, copy the current subscription address and replace the old entry in the app rather than adding a second one. If the current address still returns something the app cannot read, the fix has to happen on their side.

If the wording you are looking at is not exactly this one, compare it against the full list of messages — the eight are worded similarly and each points at a different stage.