> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://help.myndr.nl/sitemap.xml
> Use this file to discover available pages before exploring further.
> Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash).

# The Chromebook filters incorrectly

The extension on the Chromebook is linked to the student's account. If the student changes class or if the wrong class code has been entered, the Chromebook does not filter correctly.

Check whether the Chromebook is set up correctly. To do this, first click the Myndr icon in the Chrome browser and then the cogwheel icon. (If the Myndr icon is not visible, [look here](/en/article/the-extension-is-gone-i-no-longer-see-the-myndr-icon-f4c1vq/).)

![](https://storage.crisp.chat/users/helpdesk/website/5d85cd828c1b4400/myndr-extensie-opties_1aqhzc0.png)

Check whether the Chromebook is following the right Myndr Switch.

![](https://storage.crisp.chat/users/helpdesk/website/5d85cd828c1b4400/myndr-extensie-instellingen_hp2dlh.png)

If the Chromebook is not following the right switch, you can reset the extension. The Chromebook will then immediately ask for a new class code, and you cannot visit any websites as long as no class code has been entered.