Adobe, because of all the patching issues they have been having, have gone to a quarterly patch cycle that affects Mac, Linux, and Windows.  Simply put, update for free to Adobe 9.2 Reader, for free, at http://www.adobe.com/go/EN_US-H-GET-READER and get the new version.   If you are using Acrobat Pro, please follow the update procedure in the help menu of that program.

If you have a Mac, by default, there is a program called “Preview” that you probably use and unless you went out of your way to install Adobe Acrobat, you don’t have it….