A single sign-on (SSO) method is one of the most efficient authentication strategies for using web applications efficiently because users can sign in to all related services with only one-time authentication. Since SSO reduces the number of logins, several approaches related to SSO have been proposed during the past several years. However, existing schemes do not support general application systems for both web browser-based services and client program-based services. Thus, their methods need middleware or portal server to provide SSO. Moreover, existing approaches do not guarantee token authentication algorithms for SSO, and their papers need connections between the services. In this paper, we propose a novel approach of a SSO method through registry and web service methods that support general application systems without these existing limitations. Also, our method is implemented in an enterprise environment.