In this article I am going to describe "How to add SilverLight Web part in SharePoint 2010 site in very easiest way".Once you are done with your SilverLight Application then follow the following steps:1. Go to SilverLight application Bin folder and find .XAP file.2. Copy that file and paste it into 14 Hive folder on this path "C:\Program Files\Common Files\Microsoft Shared\web server extensions\14\TEMPLATE\LAYOUTS\ClientBin"You could also make your own folder to put you .XAP file.Now go to your SharePoint site.1. Open the required page into Edit mode (where you would like to place your Web part)2. Go to Insert tab-> Web part and select SilverLight web part from these as shown in given below image
Features in SharePoint designer 2010
Contributor settings in SharePoint Designer 2007
Hey..i have done the same to deploy the silverlight web part but i'm getting this message"Could not download the Silverlight application or the Silverlight Plugin did not load. To re-configure the Web Part or to provide a different Silverlight application (.xap), open the tool pane and then click Configure." My XAP file size is 421kb and MIME settings are properly configured to XAP file,is there