“Unable to start debugging. The Silverlight managed debugging package isn’t installed.”
The reason behind this is you are not installed Silverlight Developer in your system or not the latest version of Silverlight Developer version installed.
The latest version of Silverlight Developer (Silverlight_Developer.exe) set up file can find at the following URL
In sometime, you will be getting message "A newer version of Silverlight is already installed" while installing the Silverlight Developer setup file. This occur because of the silverlight runtime installed newer version (may be Silverlight v4.0 - now it is latest version) and the you have installed developer runtime already which required to be upgraded to newer version.
To fix this issue, download the Developer from the following link and install the new Silverlight Developer runtime.
If you still getting the issue, try to uninstall Silverlight runtime, Developer runtime and install the correct Silverlight runtime and the developer version what you need.
For information, the sequence of installation setup steps I follow to develop Silverlight 3.0 applications with WCF RIA services are:
- Visual Studio 2008
- Visual Studio 2008 SP1
- Silverlight Runtime 3.0 (Silverlight.exe) (http://go.microsoft.com/fwlink/?LinkID=149156)
- Silverlight 3.0 Tools (Silverlight3_Tools.exe)
- Silverlight Developer (Silverlight_Developer.exe)
- RIA Service (RiaServices.exe)