Word 2000 installation starts while loading

I am using FCKeditor on a forum I have, and like it a lot. Unfortunately, some of my users are not able to use it, since a Word 2000 installation starts whenever the editor loads. I haven't got the problem myself. What can cause this, and more important, what is the solution? I have tried to enable config.ForcePasteAsPlainText and disable config.AutoDetectPasteFromWord, as this was the only connection to Word I could find. It didn't help.