Not able to view application in IIS after successfully calling below method: ServerManager serverMgr = new ServerManager(); Configuration config = serverMgr.GetApplicationHostConfiguration(); ConfigurationSection isapiCgiRestrictionSection = config.GetSection("system.webServer/security/isapiCgiRestriction"); ConfigurationElementCollection isapiCgiRestrictionCollection = isapiCgiRestrictionSection.GetCollection(); //ConfigurationElement addElement = isapiCgiRestrictionCollection.CreateElement("add"); //addElement["path"] = @"C:\Inetpub\wwwroot\"; //addElement["allowed"] = true; //addElement["groupId"] = @"ContosoGroup"; //addElement["description"] = @"Contoso Extension"; //isapiCgiRestrictionCollection.Add(addElement); //serverMgr.CommitChanges(); Site defaultSite = serverMgr.Sites["PharmaConnect"]; defaultSite.Applications.Add("/blogs3", @"C:\inetpub\wwwroot\blogs1"); serverMgr.CommitChanges(); I don't know how to create dynamically sub domain though c# code. We just tried to implement above. But unable to view application/virtual directory in iis. I have tried this, but didn't get success.