What browser and OS, including versions? From where are you trying to download Reader?
Internet explorer and windows 8
That is either a very early alpha version, or a typo -- let's assume that you mean Windows 7.
Let's also assume that you want the latest Adobe Reader English version; download it from http://ardownload.adobe.com/pub/adobe/reader/win/9.x/9.3/enu/AdbeRdr930_en_US.exe