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Download and install Okapi Longhorn as shown here: http://okapiframework.org/wiki/index.php?title=Longhorn#Download_and_Installation.
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Previously we did run into a bug or problem with Okapi, that lead to a dysfunctional Okapi with Tomcat 8 and Okapi M35. So if you run into further problems, either try to set up a newer Okapi version or if you already have the latest Okapi version try to set it up with Tomcat 7 (with JVM 1.7.0_151-b01Oracle Corporation ) or Tomcat 9 (as shown above). The current code block shows the installation of tomcat8. However it seems, that due to a bug in Okapi Longhorn the conversion routines needed by translate5 do not work correctly with Okapi Longhorn running under TomCat 8. Yet with TomCat 7 and the correct Java Version, everything seems to work fine. For more details see https://groups.yahoo.com/neo/groups/okapitools/conversations/topics/4593?reverse=1see attached PDF file..
Translate5 Configuration of the Okapi Plug-In
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