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'

    This sometimes happens when the Java WebStart setup is not correct. WebStart keeps a list of Java versions that it uses. If some of these entries are wrong or outdated, this misleading error message may appear.

    To correct this:

    1. Start Java WebStart on its own, either from the Start menu (for Windows users) or from the hard drive in the folder 'jre/javaws' of your Java 1.4 installation.
    2. Open File - Settings and select the 'Java' tab.
    3. Check to see if the entries given there point to existing folders and files on your hard disk. Remove or correct any invalid entries.
  3. Poseidon does not start. What do I do?
  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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