Neither BindingResult nor plain target object for bean name 'command' available as request attribute

Hi I am getting exception Neither BindingResult nor plain target object for bean name 'command' available as request attribute when run login form with <form:form> tags. It works fine with normal html code but spring's form tag giving be this exception. Please resolve. I am posting few files of code as below.
Login.jsp

Web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
	 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
	 version="3.0">
	 
	<listener>
			<listener-class>
				org.springframework.web.context.ContextLoaderListener
			</listener-class>
	</listener> 
	
	<context-param>  
        <param-name>contextConfigLocation</param-name>  
        <param-value>  
            /WEB-INF/dispatcher-servlet.xml  
        </param-value>  
    </context-param>  
    <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>

<servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>*.html</url-pattern>
    </servlet-mapping>

<welcome-file-list>
        <welcome-file>/Login.jsp</welcome-file>
    </welcome-file-list>

<session-config>
        <session-timeout>30</session-timeout>
    </session-config>
</web-app>

Dispatcher_Servlet.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"    
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"    
    xmlns:context="http://www.springframework.org/schema/context"    
    xmlns:mvc="http://www.springframework.org/schema/mvc"    
    xsi:schemaLocation="http://www.springframework.org/schema/beans    
                http://www.springframework.org/schema/beans/spring-beans-3.1.xsd    
                http://www.springframework.org/schema/context    
                http://www.springframework.org/schema/context/spring-context-3.1.xsd    
                http://www.springframework.org/schema/mvc    
                http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd"> 
                <mvc:annotation-driven/>
   <context:component-scan base-package="*.*"/>
   <bean name="/validUser.html" class="Controller.validLogin" />
   
   <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <property name="suffix" value=".jsp"/>
   </bean>
</beans>

Controller :

Attached is the directory structure.
Thanks.

Still not sorted.

Use the modelAttribute attribute of the Spring form tag to specify the model name you are binding to.

Thanks Bill for your reply. As i just started the use of <form:form> tags so its not clear for me yet. Can you please tell me how model attribute works & what changes should i have to apply in code to run it.

Regards.

First of all don't implement Spring interfaces like Controller or extend Spring classes like SimpleFormController. Use the modern @Controller style instead. Have a look at this tutorial to get you started. It seems hard to find up-to date blogs out there anymore.

http://krams915.blogspot.com/2010/12/spring-3-mvc-using-modelattribute-in.html

You can scroll down and look at the editpage.jsp for the modelAttribute tag in action.