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# Error: $location:nobase
$location in HTML5 mode requires a <base> tag to be present!

    $location in HTML5 mode requires a  tag to be present!

## Description

If you configure `$location` to use `html5Mode` (`history.pushState`), you need to specify the base URL for the application with a `<base href="">` tag or configure `$locationProvider` to not require a base tag by passing a definition object with `requireBase:false` to `$locationProvider.html5Mode()`:

    $locationProvider.html5Mode({
      enabled: true,
      requireBase: false
    });

Note that removing the requirement for a `<base>` tag will have adverse side effects when resolving relative paths with `$location` in IE9.

The base URL is then used to resolve all relative URLs throughout the application regardless of the entry point into the app.

If you are deploying your app into the root context (e.g. `https://myapp.com/`), set the base URL to `/`:

    <head>
      <base href="/">
      ...
    </head>

If you are deploying your app into a sub-context (e.g. `https://myapp.com/subapp/`), set the base URL to the URL of the subcontext:

    <head>
      <base href="/subapp/">
      ...
    </head>

Before AngularJS 1.3 we didn't have this hard requirement and it was easy to write apps that worked when deployed in the root context but were broken when moved to a sub-context because in the sub-context all absolute urls would resolve to the root context of the app. To prevent this, use relative URLs throughout your app:

    <!-- wrong: -->
    <a href="/userProfile">User Profile</a>

    <!-- correct: -->
    <a href="userProfile">User Profile</a>

Additionally, if you want to support browsers that don't have the `history.pushState` API, the fallback mechanism provided by `$location` won't work well without specifying the base url of the application.

In order to make it easier to migrate from hashbang mode to html5 mode, we require that the base URL is always specified when `$location`'s `html5mode` is enabled.