This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
1) weblogic.management.console.applets.Navapplet class comes with weblogic.jar. can you check whether your weblogic.jar file contains with that class or not. 2) Both of this can happen because of your machine environment is unable to run javaapplets. Configure your java runtime for that.