Cannot reinstall windows installer

[Queenogreen]

I bought norton internet security 2005. When trying to install it, a message
comes up that says I need to install windows installer. When I click the
"yes" to install, it briefly shows an install window. It never reaches the
end and then goes away. I have downloaded the installer from the
microsoft.com site but even after installing it, the norton program says the
same thing everytime. Now I have uninstalled something that had to do with a
norton product I got online but it seems that it took away some other reqired
files and when I reboot it says something about device file missing. I have
even reformatted the computer(twice) trying to get it fixed and back in full
but I am having the same problem. I have no security at all on my computer
and can not load any. I really need help. I am just a beginner with this
computer stuff.