Problems may arise while downloading pdf's as a direct result of software revisions. Common reasons are Browser, Reader and or Plug-In software updates your computer may need. The quickest way to download files when pressed for time is the following:
Right-Click the form you are trying to download and in the pop-up window select, "Save Target As", "Save Link As" or "Save As" and direct the file save to your Desktop.
When the file downloads, open it from the Desktop instead of allowing it to open from your Web Browser. This will launch your PDF Reader software separately allowing proper access to the file.