Website is broken in IE due to "SEC7113: CSS was ignored due to mime type mismatch"

I am doing web designing using bootstrap. But Internet Explorer 8-10+ refuses to load the CSS files due to "CSS was ignored due to mime type mismatch"

1. On your computer search for "regedit.exe" (go to the start menu and click on the search button on the top-right corner of the screen).
2. Once regedit opens up, on the left column click on "HKEY_CLASSES_ROOT" and then on ".css"
3. On the right column double-click on "Content Type". This will open up a dialog box with value as application/x-css.
   
4. Change this "value data" to "text/css".
5. 
6. Click "Ok" and that's it.