The following goes from post: http://blog.csdn.net/wqjsir/article/details/7169838
Symptoms:
Tomcat can start normally in eclipse, and access to http://localhost:8080/in the browser is not accessible and is reported as 404 error. Other project pages cannot be accessed at the same time.
Close the tomcat inside Eclipse, double-click Startup.bat in the Tomcat installation directory to manually start the Tomcat server. Access htt://localhost:8080/can access the Tomcat administration page normally.
Symptom causes:
Eclipse redirects the Tomcat Project publishing directory (WebApp in the Tomcat directory), so you will find that your project file cannot be found in the WebApp directory under the Tomcat installation directory.
Workaround:
Reconfigure the following Tomcat server:
On the server page in Eclipse, double-click the Tomcat service to see the configuration page:
You can see that the red circle is selected with the Use workspace metadata (does not modify Tomcat installion)
If a project is deployed in this tomcat, the options in the red circle will be grayed out and cannot be modified, and the modifications must first be removed from the deployed service in Tomcat.
By right-clicking the Tomcat server, select Add and remove to remove the deployed project in the popup dialog box. When you are finished removing the OK, you will see the Options Panel section above editable.
Select the Use Tomcat installation (Task control of Tomcat installation) to select Tomcat's installation directory as the publishing directory for the project.
Then, down four lines, see "Deploy Path"? The value behind it defaults to "Wtpwebapps", which is changed to "WebApps", which is Tomcat
The name of the folder in which the item is published. After modification, turn off the page and save the configuration. This deploys the project to the WebApp in the Tomcat installation directory
Restart the Tomcat server, access to the http://localhost:8080 will be able to access the normal, your own deployment of the project is also able to access.
Invalid startup Tomcat in Eclipse, while manual start can be accessed for reasons