Links to local files it seems ahve been disabled in the latest
versions of Google Earth.
Do you have any sort of intranet you could link to? Possibly even a
webserver than can serve up files from your local network? Or maybe
you have some sort of search that you could link the specific page for
the file?
Another possibilty (but not sure its actully a good idea, mainly as it
creates lots of copies of your files) - is to package up the file
inside a kmz, I think GE still allows lauching files from inside
archives (but then again that functionality might go too!)
(btw I take it the opening comment is a typo, rather than vent of
frustration ;)