As you know Silverlight is a cross-browser plug-in which means that the code will be executed on the client's machine. Thus, you cannot assume that every user will have an image with the exact name or location. Rather you should include the image in your SIlverlight or Web application and refer the image to it. The path to the image depends on the build action of the Image itself. Here
is a good example that demonstrates all possible ways you can load an image in a Silverlight 2 application, which is essentially the same for Silverlight 3.
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