Whenever the webmaster generates a new event source in the event log, the server does not allow to access and displays this security block error. The user's account might not have any right to generate an event source in the event log using ASP.NET. Before executing the ASP.NET Application, the webmaster holding the rights should create an event source. The procedure for creating this application event log in registry editor is given in the article. This article helps the users to use the registry editor in a proper way. Sample in Visual C#.NET is also added with this tutorial for the understanding of the users.