我现在开发PDA我配置好后..在程序中却说"请数据发送到运行的IIS计算机请求失败"

我现在开发PDA我配置好后..在程序中却说请数据发送到运行的IIS计算机请求失败

程序如下:
private void GetDownDataBase()
{
string localDatabase=@"\chun.sdf";
string localconntiomstring = "Data Source=" + localDatabase;
string remoteConnectionString = @"Provider=sqloledb;" +
"Data Source=chun;Initial Catalog=chun;" +
"Integrated Security=SSPI;";
string[] tables = new string[] { "student", "scouse" };

if (File.Exists(localDatabase))
File.Delete(localDatabase);
SqlCeEngine engine = new SqlCeEngine(localconntiomstring);
engine.CreateDatabase();

using (SqlCeRemoteDataAccess rda = new SqlCeRemoteDataAccess())
{
rda.InternetUrl = "http://chun/server/sscesa20.dll";
rda.LocalConnectionString = localconntiomstring;

foreach (string table in tables)
{
try
{
rda.Pull(table, "SELECT* FROM [" + table + "]", remoteConnectionString, RdaTrackOption.TrackingOffWithIndexes, "ErrorTable");
}
catch (SqlCeException ex)
{
MessageBox.Show(ex.Message + ex.InnerException,"天伦软件提示！" );

}
}
}

}
在IE中输入http://chun/server/sscesa20.dll测试是正确的..请高手指点.....
QQ:112223304谢谢......