During testing I found situation that SCAYT stop working on IE8. 1. Use system with Internet Explorer 8 browser 2. Open sample (new or some old one): * http://cdn.ckeditor.com/4.10.0/full-all/samples/ * http://cdn.ckeditor.com/4.6.0/full-all/samples/ 3. Try to enable SCAYT Result: Error in console appears 