If it is the problem with dynamic ports then try this...NOTE: im using VSTS 2008
Go to solution explorer ==> Click (no right click) on web application which gets created by silverlight app. ==> Press F4 in the keyboard.
A Dockpanel shows up you can set there properties such as , Always use dynamic ports and set ports.
If you are using other than VSTS 2008...i just right click on the web project and Properties. and there you can set port hopefully.
Thanks
Rajesh Shirpuram
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