Sorry! An error has occurred.

1) Maybe your browser does not support JavaScript or it is not enabled.

2) If you are watching this ISO-8859-1 (western) version on a non-latin operating system, with old versions of certain browsers you have to set the type of encoding manually.
Find the preferences in one of the menus, choose character set / Encoding, and check Western ISO-8859-1.
If you want to display French accented characters in generated text, you also have to choose ISO-8859-1 as your default encoding
After setting the character set, click Reload (in the top menu) once or twice.
This problem does not occur in recent versions of the popular browsers.

3) With certain browsers, when you resize a window containing several frames, when you change the font encoding and in various other circumstances, only the parent window is repainted.

Please, click on "Reload" in the top menu of your browser.

If you were in the middle of an exercise, well,
we are afraid you might have to start all over again...