Drools eclipse rule editor throws an error when opening or saving a drools file ------------------------------------------------------------------------------- Key: DROOLS-1083 URL: https://issues.jboss.org/browse/DROOLS-1083 Project: Drools Issue Type: Bug Components: eclipse plugin Affects Versions: 6.4.0.CR1 Environment: Spring Tool Suite Version: 3.6.4.RELEASE Build Id: 201503100339 Platform: Eclipse Luna SR1 (4.4.2) MacBook Pro (Retina, 15-inch, Late 2013) OSX 10.10.2 Reporter: Ido Flax Assignee: Robert (Bob) Brodt Attachments: Screen Shot 2016-03-08 at 10.25.26.png I downloaded the Red hat jboss developer studio tools plugin for eclipse and since then whenever i open or save my drools file or switch to it's open tab i get this error: {code:java} An error has occurred. See error log for more details. Could not initialize class org.kie.internal.utils.ServiceRegistryImpl {code} This also prevents the drools compiler from showing me errors or problems with my drools code. I'll also mention that it randomly stopped doing it at some point but when i closed and reopened my eclipse it started again