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?
  4. How can I run Poseidon in a different language?

    Poseidon currently supports the following languages:

    • English (United States)
    • German (Germany)
    • Spanish (Spain)
    • French (France)
    • Portuguese (Portugal)
    • Chinese (Taiwan)

    Further localizations are planned. If you are interested in helping with your language, please contact us at

    To change the language used:

    1. Open the Settings Dialog from the Edit menu.
    2. Select the desired language from the drop-down list.
    3. For some items, the change takes effect immediately. However, some elements might change only after a re-start of Poseidon.
  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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