Setup program needs framework 4.0 - But it's already installed

I created a service which I now want to install to test. When running the setup program it prompts me to download and install .net fw 4.0, but I already have it installed. I did try to just install the file that I get pointed to (4.0 cliet), but not only does it still not work, it causes vs2010 to throw an unknown error and can't open.

I've now uninstalled everything and started afresh with VS2010, framework 4.0开发者_JAVA百科 and win 7 but it still prompts me to install fw 4.0 when I try to run the setup. Can anyone please point me in the right direction?

Thanx in advance Willem

Here are some ideas:

1. I assume you have rebooted your machine; if not, do this and try again.
2. See this page about verifying your .NET 4.0 installation.
3. Using IE, go to http://whatsmyuseragent.com/ and ensure that .NET 4.0 is shown.
4. In VS 2010, write a small console app that outputs Environment.Version.ToString(). This is the .NET CLR version. Run this app from outside VS 2010, and ensure it works as expected.
5. At this point the problem is most likely with the installer used to create the service. Please add more information about it.