Right mouse click the file, select 'open with' and re-confirm Adobe Reader is the default. If it isn't, correct it.
i tried it with every file to make sure its on adobe,but its already on it.
when i open it with adobe it says'' adobe reader could not open file..because its not a supported file or been damaged''.
when i downloaded the samepdf file from same site on windows xp, it opened with no problem.