The MSI installer is responsible for installing most system-related programs in Windows 7. If you get the "Windows installer has stopped working" message when installing a program, it means that there is a problem with the MSI installer. Therefore, you should repair the MSI installer if you are to install any programs through it. Windows 7 allows you to repair it by manually running a single command on the Command Prompt console.
Open the Windows 7 Command Prompt as an administrator. To do so, click the Windows logo on the Windows 7 taskbar and then click "All Programs." Next, click "Accessories" and then right-click on the program labeled "Command Prompt." Click "Run as Administrator" on the drop-down menu and then click "Yes" on the "User Account Control" dialog box.
Type "reg delete HKLM\SOFTWARE\Microsoft\SQMClient\Windows\DisabledSessions /va /f" (without quotes) into the Command Prompt window and press the "Enter" key to fix the MSI installer.
Click the "Close" button after fixing the MSI installer to close the Command Prompt window.