1. Tomcat running independently is not closed. 2.Tomcat has been running before, or Tomcat is abnormally closed, and Tomcat still exists in the process.

3. The port used by Tomcat is occupied by other software (the default port of Tomcat is 8080).

Solutions to these errors:

1. In the system service, change the startup mode of Tomcat from "automatic" to "manual" (by default, Tomcat is an automatic startup service, starting from startup).

2. Shut down the Tomcat running independently, and make sure to stop the Tomcat service before Eclipse starts Tomcat.

3. Check the Task Manager to see if there is Tomcat in the process, and if there is, close it.

4. If starting Tomcat in Eclipse is still unsuccessful, the port of Tomcat may be occupied.

A. find the server.xml file: ... \Tomcat 5.0.28\conf\ under the Tomcat path, retrieve the port number: 8080, and change it to an unoccupied port number, such as 8088.

B. You can use the command under dos: netstat -a to check the usage of the port and see if the port of Tomcat is occupied by other software.