Repair MSI (Windows Installer):

This will try to repair the Windows Installer (MSI)

The following commands are ran:

The MSI Server service is also replaced.

sc config msiserver start= demand
Net stop msiserver

MSIExec /unregister
MSIExec /regserver
regsvr32.exe /s %windir%\system32\msi.dll

Net start msiserver

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Here is a complete set of steps that should allow you to repair the Windows Installer service on a 64-bit OS:

    Click > Start >  Run.
    Enter cmd and click OK.
    Run the following commands:

%windir%\system32\msiexec.exe /unregister
%windir%\syswow64\msiexec.exe /unregister
%windir%\system32\msiexec.exe /regserver
%windir%\syswow64\msiexec.exe /regserver


    Restart the computer.
    Retry installation


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Method Four. Reinstall Windows installer

If all the methods above all fail to help you, the last choice is to reinstall the Windows installer. 

1. At the start, search for CMD.
2. At the command prompt, type the following lines. Press ENTER after you type each line.
   cd %windir%\system32
   ren msi.dll msi.old
   ren msiexec.exe msiexec.old
   ren msihnd.dll msihnd.old
3. At the command prompt, type exit, and then press ENTER.
4. Restart your computer.
5. Update the Windows Installer files to the latest version. To do so, visit the Microsoft Web sites, and then download and install Windows Installer.
6. After the installation of the Windows Installer is complete, shut down and restart your computer normally before you install programs.