known issues with vista/ac-decal typically center around where software was installed and level of authority trying to run software under.
i 'beleive' the standard default directory vista tries to stick the stuff in/under doesn't have all the proper permissions to read/write or authority levels that are required.
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Ag Nar
Portal Mule Master of the Loresraat
Mastering the pixels of gamedom, 1 MMORPG at a time..