I was upgrading the tomcat in my eclipse from version 6 to 7. Servers were added, old servers were removed. Tomcat 6 installed. But the server is not starting because of the following error.
Target runtime Apache Tomcat v6.0 is not defined. <project name> Unknown Faceted Project Problem
It keeps my old server entry for the project.
We need to right click on the project, properties and Targeted Runtimes. Uncheck the old entry and enable the new entry. This should solve this error.
Still server is facing some other issue. Need to check up.