I work in Desktop Support for the Forest Service & I have found that sometimes when uninstalling an application that the un-install did not correctly remove the application from the computer. In those type of cases the Windows registry still has remnants of the application so when you try and re-install the application it won't install because of thos remnants (many times when you look in Control Panel--- Add/Remove Programs, it will appear that the progrm is not installed!)
You can use a tool provided by Microsoft to remove those remnants called msicuu2.exe I'm not sure where to get it, so just Google that name and you should be able to find it.
This tool will show all the applications currently installed as well as the application which is really only remnants in the registry. He will select ONLY Adobe reader in this utility and remove it (IF it appears as one of the applications which is in his computer). If Adobe Reader does NOT appear as one of the applications which can be removed then we have a differnt problem and need to proceed with further troubleshooting.
You may want to try the following.
Remove all traces of Reader (not only the program) from your system using the Windows Installer Cleanup Utility. This is no longer supported by Microsoft because it can produce problems with Win 7, but you can still download it from from places like
Then, download the Reader installer from
and perform a clean install.