It sounds like a problem described in mskb #Q319949 Error Message: "A File That Is Required to Run Search Companion Cannot Be Found".

>Hi everyone.
>
>Since a few days ago i'm having this problem with WIN XP:
>
>When i go to start menu and then search and then for files and folders, my Win XP tries to open the dial-up connection and tries to connect to my ISP, when i cancel dial-up the search can't open and tells me something like there's a file missing in the search companion, need to run setup again. I wish somebody could tell me how i got this, why is this happening, is there a way to solve this???. I need the windows search because sometimes i forget some locations of my files.
>When i'm connected to Internet i can't dare to try to go to the search because my PC will crash and i have to reebot.
>
>Any ideas?? Any reasons for this??
>
>Jim.