It is not finding the controllers, this is basic issues.
it can be due to following reasons.
A. inside WEB-INF folder you have file web.xml that refers to dispatcherServlet. Here it this case is mvc-config.xml
<servlet>
<servlet-name>dispatcherServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/mvc-config.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
B. This mvc-config.xml file have namespaces and it has to scan the controllers.
<context:component-scan base-package="org.vimal.spring.controllers" />
<mvc:annotation-driven />
C. Check for the correctness of the package name where you have the controllers. It should work.
All Controllers must be Annotated with @Controller.