IIS 6 .NETruntime 2.0 error reporting

Oct 16, 2008 at 8:24 PM
I have an app based on 1.6v Facebook developer toolkit.
My server is a Windows 2003 with Framework .net 2.0
My app is write in C#

After recently Facebook updates, I'm trying to migrate to Facebook developer toolkit 2.0.
I include new dll and files, then I change all my call functions to work with new API, but When I try to run my app, return an error (System.xml.linq).
After reading I belive that problem is that I have to install Framework .NET 3.5 becasuse some libraries are referenced.
When I install .NET 3.5 my IIS crash, I can't see in event view this error: .NETruntime 2.0 error reporting
I can't see anymore. After this, some times IIS said: "service unavailable"
I belive that the problem is Linq, but I don't Know.

Someone can help me?