Internet Explorer Script Error
An error has occurred in the script on this page.
(worthless line and character info)
Error: Class not registered
Code: 0
URL: (domaininformation)/FCKeditor/editor/dialog/fck_image.html?ImageButton
LATE LATE UPDATE:
This error actually even occurs on the FCKeditor's own demo now, so I'm very confident it's something Microsoft has done, probably with the Java engine.http://www.fckeditor.net

Re: IE Image Browser "Class not registered" error
Could you try to use a restore point in any of those computers to the previous week? (and check also what changes have been done in that time.
Re: IE Image Browser "Class not registered" error
On one of our computers that has not had the Microsoft update and it still works.