Frequently Asked Questions   Sections

The Gentleware FAQ is a comprehensive list of questions regarding Poseidon for UML. At this time, third-party plug-ins and products are not covered in this FAQ but we plan to add them in the future. Further information is available from the Poseidon documentation or you can post to our forum.


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FAQ Section: Download, Installation, First Start
  1. What do I do when the Installer says "Magic number did not match" ?
  2. WebStart stops with the error 'Wrong Certificate used to sign resource'
  3. Poseidon does not start. What do I do?

    First, make sure that you have installed Java 1.4.0 or higher. The recommended version is Java 1.5.0_04. If you are not a Java developer and you do not need to compile Java code from within Poseidon, it is sufficient to download the JRE (Java Runtime Environment), You will find it in section Download J2SE v 1.4.2.

    Java 1.4.2_03 or higher is required for Community Edition if started via WebStart.

    If you start Poseidon using the Windows Start menu, verify that the link points to the installation of Poseidon.

    To verify the link location:

    1. Open the Start menu and navigate to view the Poseidon icon.
    2. Right-click on the Poseidon icon in the Start menu and select 'Properties'.
    3. The link location will be displayed.

    If you use startPoseidon.bat or, make sure that the environment variable JAVA_HOME points to a Java JDK directory.

    To verify the environment variable in Windows:

    1. Open the Control Panel and select 'System'.
    2. Click the 'System Variables' button from the Enhanced tab.
    3. Review the value of JAVA_HOME.

    To verify the environment variable in Linux:

    1. From a command prompt, type echo $JAVA_HOME.
    2. If nothing is shown, type export JAVA_HOME=(your JDK directory) and then start Poseidon.
    3. You should add this command to your .bashrc (or the comparable file for the shell you are using).

    If Java is found but still Poseidon refuses to start, make sure that you are using a recommended version of Java.

    If you use the installer starter, you can change poseidon.user.home for the starter program by editing the Poseidon_for_UML.lax in the installation directory. To do this, simply edit poseidon.user.dir. and point it to the desired home directory.

  4. How can I run Poseidon in a different language?
  5. How can I move/rename Poseidon's configuration directory?
  6. " name length exceeds 512 bytes" exception when starting the Embedded Edition
  7. "Invalid command line switch: -xmx192m" error on first start
  8. What do I do when the installer does not start?
  9. Why do I get a ClassNotFoundException when starting Eclipse with Poseidon installed?
  10. How do I use the installer with Windows 2003?
  11. Why aren't my EE clients connecting to the EE server when the server runs on Linux?
  12. Why does my server using RMI connot be connected?
  13. I get an OutOfMemoryException when using Poseidon with Eclipse. What can I do?
  14. How do I use the installer with Windows Vista?

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