I have installed trial version on Jira 5.2.2. When I tried to install the Greenhopper from, I get the following error
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I also tried to download the plugin (jar) file separately and upload the plug in, still getting an error while Enable with some unknown error.
I did tried by removing the .bundled-plugins and .osgi-plugins and there are no JAR files under my $JIRA_HOME/plugins/installed-plugins. But no luck yet.