Hi All I am fail to install Sliverlight3 tools for VS2008 SP1 Following Error shown in log file WinHttpDetectAutoProxyConfigUrl failed with error: 12180 [3/12/2010, 10:51:12] (IronSpigot::WinHttpDownloader::GetProxySetting) Auto detection of proxy failed, try to retrieve proxy information via IE. [3/12/2010, 10:51:12] (IronSpigot::WinHttpDownloader::GetProxySettingViaIE) Retrieving proxy information using WinHttpGetIEProxyConfigForCurrentUser [3/12/2010, 10:51:12] (IronSpigot::WinHttpDownloader::GetProxySettingViaIE) Unable to retrieve Proxy information although WinHttpGetIEProxyConfigForCurrentUser called succeeded [3/12/2010, 10:51:12] (IronSpigot::WinHttpDownloader::CreateSession) WINHTTP_ACCESS_TYPE_DEFAULT_PROXY [3/12/2010, 10:51:12] (IronSpigot::WinHttpDownloader::StartDownload) Session Created [3/12/2010, 10:51:12] (IronSpigot::WinHttpDownloader::StartDownload) Connection Created [3/12/2010, 10:51:12] (IronSpigot::WinHttpDownloader::StartDownload) Request Created [3/12/2010, 10:51:12] (IronSpigot::WinHttpDownloader::AsyncCallbackInternal) WINHTTP_CALLBACK_STATUS_REQUEST_ERROR error: error=12007, result= 5. Percentage downloaded=-2147483648 [3/12/2010, 10:51:12] (IronSpigot::RetryingDownloaderT<class IronSpigot::WinHttpDownloader,class IronSpigot::BitsDownloader,class IronSpigot::UrlMonDownloader,class IronSpigot::FileAuthenticity>::DownloadUsingUrlMon) Cannot resolve server name (12007) when downloading using WinHttp, try using URLMON [3/12/2010, 10:51:12] (IronSpigot::UrlMonDownloader::PerformAction) UrlMon download failed with 800c0005 [3/12/2010, 10:51:12] (IronSpigot::RetryingDownloaderT<class IronSpigot::WinHttpDownloader,class IronSpigot::BitsDownloader,class IronSpigot::UrlMonDownloader,class IronSpigot::FileAuthenticity>::PerformAction) Download failed at attempt 1 of 4 for http://go.microsoft.com/fwlink/?LinkID=150219 using http: [3/12/2010, 10:51:12] (IronSpigot::RetryingDownloaderT<class IronSpigot::WinHttpDownloader,class IronSpigot::BitsDownloader,class IronSpigot::UrlMonDownloader,class IronSpigot::FileAuthenticity>::UseHttp) Determine the protocol to use [3/12/2010, 10:51:12] (IronSpigot::BitsDownloader::InitializeBITS) Failed to COCreateInstance BackgroundCopyManager : hr= 0x80070422 [3/12/2010, 10:51:12] (IronSpigot::BitsDownloader::InitializeBITS) Failed to COCreateInstance BackgroundCopyManager : hr= 0x80070422 [3/12/2010, 10:51:12] (IronSpigot::RetryingDownloaderT<class IronSpigot::WinHttpDownloader,class IronSpigot::BitsDownloader,class IronSpig