Unable to open installer

[Permenion]

Ok, so I downloaded the RS II files needed for the installation (msi, setup and the 4 cabs)
I downloaded all from filefront, but my computer didn't recognize the setup as a setup.
So I redownloaded it from megaupload, and he recognized that one. The problem is, every time I click on the installer, windows shows an error message (white cross in red circle) with the following msg:

(translated from Dutch) "Unable to open this installer. Contact the supplier to see if this is a valid Windows installer package"

Answers?

Additionnal information:
-OS: Windows 7 (32 bits.. or 64?)
-Files are NOT stored in a Program Files Section
-Install path: not chosen, since I can't open it
-Steam? No
-RTW version 1.5
-installer option: RSII Windows installer file (.msi) (doesn't open)
RSII Setup doesnt open either
-tried to open in compatibility with vista and xp, none works...

-Permenion


EDIT: Strangely enough, I copied the installer my bro downloaded from filefront (so eaxactly the same file) and it now works.

[Paedric]

Resolved then?