Close Processes
1. Complete or close any software installation processes underway on your computer.
2. Right-click the task bar at the bottom of your desktop and select 'Start Task Manager' from the context menu.

3. Click the 'Processes' tab and then click 'Show Processes From All Users.'
4. Look for running processes with names like 'setup.exe,' 'msiexec.exe,' 'uninst.exe,' 'isetup.exe,' 'ikernel.exe' or 'IsInst.exe.' For each of these processes that you find running, click on the entry and then click the 'End Process' button.
5. Try running the installer again.
Re-register Service
6. Click 'Start,' 'All Programs' and then 'Accessories.' Right-click on 'Command Prompt' and choose 'Run as Administrator.'
7. Type 'Msiexec /unreg' (without quotes) into the command prompt window, then press your 'Enter' key to unregister the Windows Installer service.
8. Type 'Msiexec /rereg' (without quotes) into the command prompt window and press 'Enter' to re-register the Windows Installer service.
9. Try running the installer again.