That means that your oak version in aem does not match the oak-run you're using to find the last revision.In my case I had to use the 1.2.18.full instructions. 1. Download oak-run jar file from here http://repo1.maven.org/maven2/org/apache/jackrabbit/oak-run/   * AEM6.1 - Download the oak-run 1.2.x ...