Install Office 2010 under Windows 7 if error 1719: Unable to access the Windows Installer service. This can occur when Windows Installer is not installed correctly. Contact your technical support staff for assistance. "This error description is due to problems with Windows Installer and can be resolved in the following way."
Press the "Win + R" key combination to open the Run dialog box, enter "Services.msc", and open the Services Feature window.
Locate the Windows Installer Service in the window.
Double-click to open the Windows Installer Service dialog box, set the startup type to Automatic, and click on the service status "Start" button, and then "OK".
Locate the Cmd.exe file under C:windowssystem32 on your computer, right-click and select Run as Administrator.
Enter "regsvr32 msi.dll" in the Command line window, return, prompt "DllRegisterServer succeeded in Msi.dll" and "OK" to exit.
Reinstalling Office 2010 solves the problem.