Download the latest version of Adobe Reader. This link will take you to the first page. Scroll to the bottom, fill in the required fields and click the Download button. If no download window appears for a long time, click back to the previous page and choose an alternate source, right below the download button. If you choose the alternate source, just select the first link on the new page.
After installing Acrobat Reader, you must close your browser and start your browser again so the changes will take effect.