Windows Installer 4.00.6000.0 in Windows Vista

Hello,
I've installed the operating system Windows Vista Home Premium and the
version
Windows Installer 4.00.6000.0.
I am trying to uninstall the package of Microsoft Office Standard Edition
2003, but I only get an error message that says: "Unable to access the
Windows Installer service. This can occur if Windows Installer is not
installed correctly. Contact staff
Assistance. "
The same thing happens when I try to install the Adobe Photoshop CS2 package.
I saw that there is no possibility to download the Windows version 4
Installer, the latest available is that the network is 3.1.
What can I do? It may be a problem of the system registry? In
This would help set up a program to cheap file
Register? Where can I find a Windows Installer 4 to download?

Also, I might add that in the "Administrator Tools\ Services", Windows
Installer is present, not running and the booting is "Manual." When I see its
properties, there's nothing written in the "Path executable", I imagine that
there should be "C: \ Windows \ System32 \ msciexec / V" instead.
Is the path to the file lost? How do I restore it?

Thanks again to everyone who can help me.