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1 severe error(s) detected!
While severe errors may not prevent the rendering of the page on mobile devices, they negatively impact the user experience. They should be addressed first.
Here is the error:
Follow the links above for a detailed description of each message and suggestions to fix the underlying problem.
Checks in this category ensure that the content is properly encoded, and that the encoding being used is properly advertised in the HTTP headers. See Introducing Character Sets and Encodings for an overview of this topic. mobileOK requires that the content be made available encoded in UTF-8.
The quality of the markup sent to mobile browsers will impact the reliability and smoothness of the rendering of the page. Markup validity is the first step to delivering content that can be parsed and rendered reliably by browsers. The recommended markup format for mobile content is XHTML Basic 1.1. But beyond validity, various tags and attributes have a specific impact in the mobile world. For instance, CSS style sheets should be used to control the layout of the page instead of presentational tags (e.g. center, big, or font) and images sizes should be defined in the markup to avoid reflows.
The source of the messages in this category is to be found in the HTTP headers that were sent along with the page. They are most likely due to the Web server configuration for static files, or the way the server-side scripts are written for dynamic content. Making sure that HTTP headers are correctly defined is essential in a mobile context with a usually low bandwidth and high latency.
Following a link may require cost, time, and attention from users in a mobile context. When a user follows a link that leads to nowhere, or cannot be rendered by the browser, the user experience is poor.