When trying to install a revision I get an error message stating that "the installation source cannot be found". If I go to Adobe Reader Help and run the repair function, i get the same message. If I try to uninstall Adobe Reader, I get the same message. Adobe Reader is functioning but can't install updates. I am using Vista OS.
Use the Windows Installer Cleanup Utility to remove Adobe Reader, then install it again.
P.S. I have heard of problems after using this tool when Office 2007 is installed. A System Restore Point is advised in this case before proceeding.