This is probably caused by an incorrect context file (Tree4Notes.xml in tomcat's conf/Catalina/localhost). The problem might be wrong syntax or wrong value in any of the parameters/attributes.
To get a clues on the exact reason, try the Start link again, and then have a look at the end of the latest logs (tersus.log in in the application's logs folder, or the various files in tomcat's logs folder).
If that doesn't help, you're welcome to reply, attaching the context (.xml) and log files (using the paper clip toolbar button).
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