Fixing WCF/WPF VS 2005 Extensions installation after installing VS 2008 or .NET 3.0 SP1

I've encountered a problem trying fix the WCF / WPF Visual Studio 2005 Integration components after I've installed Visual Studio 2008.

Installing a VS 2008 will install .NET 3.0 SP1 and remove the installation of .NET 3.0. When trying to install the WCF / WPF Extension, installation display's a message

Setup has detected that a prerequisite is missing. To use Visual Studio 2005 extensions for .NET Framework 3.0 (WCF & WPF), November 2006 CTP you must have the .NET Framework 3.0 runtime installed. Please install the .NET Framework 3.0 runtime and restart setup

You really can't install .NET 3.0 since a newer version (.NET 3.0 SP1) is already installed.

I found a solution on the MS Forums http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2550726&SiteID=1

It involves either going creating a registry key to full the installers into thinking that SP1 is installed. To fix the issue, add the following value to the registry:

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{15095BF3-A3D7-4DDF-B193-3A496881E003}]
"DisplayName"="Microsoft .NET Framework 3.0"

Thanks Erich for the solution.

Cross Posted from http://blog.tfanshteyn.com/2008/01/fixing-wcfwpf-vs-2005-extensions.html