In most cases Adobe Reader will not install after downloading if you have the "User Account Control" turned off or log on to the default administrator account in Windows Vista.

There are two way to solve this problem.

1) Navigate to the Control Panel -> User Accounts -> click Turn User Account Control on. Restart and install.

2) If the UAC is turned on, you will have to install it in Windows XP Compatibility mode. Right click on the file in the downloaded destination -> Select Compatibility Mode -> Run this Program in Compatibility Mode -> Select Windows XP.

This is a post from the www.cocosupport.com blog.