There are two potential barriers that you need to be aware of when installing from the Adobe web page:

1. What operating system is on your computer?  The Adobe download page is set for a Window XP operating system.  Your computer may have an earlier version or later version operating system, e.g. Windows 2000 or Vista, or possibly you have a Mac.  In any event by clicking on the "Choose a different version" on the Adobe webpage, you can select your operating system and download the corresponding version of Adobe Acrobat Reader.

2. The anti virus software on your computer block the download.  To overcome this you will need to click the gold banner, then click the Install Active X control window, that will let you proceed with the software download.  During the actual installation several antivirus alerts may pop up which you should also allow the installation to proceed.