Rather I would suggest, that since there are at times, if any other incompatible stuff installed, which the fuzzed up sites do not use, this causes the break in installation of Flash. I would also suggest you clear all the base files, IE. MF, GC, etc, so that the caches are deleted & also that the activex of your system is updated.
Otherwise, I would also suggest you download from the Adobe site & also while installing make sure that you are installing the compatible version, so that it works.