Michel,

Try the following link:
http://www.microsoft.com/downloads/details.aspx?FamilyID=262d25e3-f589-4842-8157-034d1e7cf3a3&DisplayLang=en

Download the file and install. If it says you've already installed the package (1.1 framework) uninstall it, and then reinstall from scratch. From my experience if the 1.1 framework is installed prior to IIS being installed, some quirky things can happen.

Hope that helps...