CLASS101 Help Center

[Available Devices, OS, and Browser/Application]

※ You may face difficulties when using unsupported device or browser, so please check playable devices and browsers first.

If you are still having trouble taking classes despite having a compatible device or browsers, please follow the tips below.

  1. Please clear the cookies and cache data from your Chrome browser.

    • Please set all data and delete data.

      • Enter "chrome://settings/clearBrowserData" on Google Chrome address bar.

  2. Please update your Chrome browser to the latest version. (Steps 3, 4, 5 will automatically applied)

    • Enter "chrome://settings/help" on Google Chrome address bar → Check the current version and update (if applicable).

    • Please keep your browser up-to-date for a seamless learning experience.

  3. Please update the DRM module to the latest version.

    • Enter "chrome://components" on Google Chrome address bar → check "Widevine Content Decryption Module" is up-to-date or update it (if applicable).

    • If "Widevine Content Decryption Module" is not being updated, please follow the steps below.

    • Update your browser → restart your browser → update 'Widevine~'

  4. Allow "Sites can play protected content".

    • Enter "chrome://settings/content/protectedContent" on Google Chrome address bar.

    • Activate "Sites can play protected content".

  5. If the video freezes frequently, please disable "Use hardware acceleration when available".

    • Enter "chrome://settings/system" on Google Chrome address bar.

    • Disable "Use hardware acceleration when available" → restart your browser.

  6. Check your antivirus software, Chrome extensions, and firewalls.

    • Temporarily disable your antivirus software and try to reaccess the video.

    • Enter "chrome://extensions" on Google Chrome address bar → turn off all extensions and reaccess the video.

※Notice

  1. Currently, there are no restrictions on the number of devices you can register for one account, but your account may be put on hold if you access the account through multiple devices simultaneously.

  2. Selling, renting, sharing or transferring account and class contents to others is strictly prohibited.