I've also had good luck with the KB article below fixing this problem.
http://support.microsoft.com/kb/211494

"Johan" wrote:

> Documents only open from within Word(when I click File then Open). Not when I
> open (double click) them in Windows Explorer or on the desktop or
> network...(Excel too)
>
> When I double-click the document in Windows Explorer, Word (Office XP) opens
> but without the document (grey background). When I then goto File, Open and
> browse, the document opens.
>
> This happens when I log into the pc with any newly created user- or
> administrator account. When I log into my WInXP with the administrator
> account which was used to install Office XP, all is well and working then. I
> have reset permissions, checked securirties, recreated docs, re-saved,
> checked Word "options"...
>
> Should I re-install Office XP? It is a workroom with 40 pc's... Ouch!
>
> Any idea why?
>
> Thanks!!!
>
> Johan
>