I presume you're referring to the instructions found in http://www.tersus.com/#Id=242.
Before installing the tersus server, have you verified that tomcat is running correctly as suggested in section 1.5?
Section 1.7 does suggest installing the server in a new directory /tersus-server/ , but this is only a recommendation ... any directory should be fine, as long as the user running tomcat has access to it.
The location should have no effect on whether the tomcat service/daemon starts successfully, but you may want to try removing the tersus server and any context files you created (see section 2), and restarting the service.
Please make sure you follow the instructions in the document precisely, and if the problem persists check the tomcat logs (@ <tomcat root>/logs ) and post your findings.
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