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If you are already running the OpenMRS Platform, then you need to add quite a few modules to be running the full Reference Application. You can get these by going to http://openmrs.org/download and looking for a link like "Download Reference Application (version number) Addons". (Make sure to get the version of the reference application that corresponds to the platform version that you are running. Unzip that file, and put all the OMOD files in your modules folder(e.g. ${HOME}/.OpenMRS/modules) or (Windows + R > %appdata%>OpenMRS>Modules), and all the OWA files in your owa folder, and restart the web server.
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