tomcat requested resource () is not available [duplicate]

Answer 1

Errors in your servlet may cause Tomcat to mark it as unavailable as I got in my server log:

06/02/2013 13:32:43 org.apache.catalina.core.ApplicationContext log INFO: Marking servlet Imager as unavailable 06/02/2013 13:32:43 org.apache.catalina.core.StandardWrapperValve invoke SEVERE: Allocate exception for servlet Imager java.lang.ClassNotFoundException com.project.test.ImageThumber

You should look the log for reasons. In my case a missing jar with some test classes.