Need some help: AVG & Missing DLL?

I'm just running some maintenance checks and decided to try out AVG. I successfully have downloaded and installed it on 2 computers. On mine, however, when I click "Setup" It tells me I'm missing SHELL.dll and something about a folder in Documents and Settings . . . Does anyone know how to solve this, or at least get that DLL.

Also, is there a program which will scan your computer and tell you the defualt missing .dll files in your computer which are windows defaults?

Thank you.

Jnick

 

you could try here.
http://www.google.com/search?q=shell.dll&sourceid=firefox&start=0&start=0&ie=utf-8&oe=utf-8

 

sfc /scannow will replace all missing system files.

 

I recently had this problem! By going into c:\windows\system and copying the shell.dll file and pasting it into c:\windows\system32. I was able to fix this issue.