by Takashi Morifusa


April 27, 2011

Thanks for sharing information

Some customer suffer from “Could not Launch” problem with “An internal error occurred.” on Fireworks CS4 on Window.

Please delete “Fireworks CS4 Panel Prefs.xml” and re-launch application. This could solve the problem.


The file location is:

Windows XP:
[Drive C:]\Documents and Settings\[username]\Application Data\Adobe\Fireworks CS4\[language]\Fireworks CS4 Panel Prefs.xml

Windows Vista or Windows 7:
[Drive, C:]\Users\[username]\AppData\Roaming\Adobe\Fireworks CS4\[language]\Fireworks CS4 Panel Prefs.xml

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  • By Jaime Creixems - 11:20 PM on April 27, 2011  

    Great! thanks, any idea where this file might be on a Mac?

    By the way I love to see you guys are blogging more frequently. The Fireworks community is bigger than can be thought and we’re desperate to get in touch and keep expanding.

    I would like to reccomend a blog from a Fireworker who’s always publishing great tutorials and resources:

    • By Takashi Morifusa - 9:56 AM on April 28, 2011  

      Thanks for the comment.

      For Mac the same Panel preference location is:
      HDD > User > [username] > Library > Preferences > Adobe Fireworks CS4 > [Language] > Fireworks CS4 Panel Prefs.xml

  • By Thierry Lorey - 7:02 AM on April 30, 2011  

    Hi Takashi,

    Hi the delete of the Panel Prefs.xml file worth for Fireworks CS5 and higher?

    • By Takashi Morifusa - 11:28 PM on May 2, 2011  

      I haven’t heard the problem occurs in Fireworks CS5 so far. We address CS4 bug already. If somehow someone encounter this problem in CS5, please let us know.


  • By Yuri Ribeiro - 10:31 AM on July 29, 2011  

    This same problem but with Fireworks CS5 but the same solution also worked with the CS5.

  • By start_to_disspoint - 12:20 AM on February 4, 2012  

    YES now happened on Fireworks CS5!
    Start to feel disappointed with Adobe product.
    Try the solution by deleting: [Drive, C:]\Users\[username]\AppData\Roaming\Adobe\Fireworks CS5\[language]\Fireworks CS5 Panel Prefs.xml

    and even the whole
    [Drive, C:]\Users\[username]\AppData\Roaming\Adobe\Fireworks CS5

    once relaunch, FW will recreate the structure of those folders again.

    STILL same problem and message displayed.

  • By English - 6:58 AM on February 14, 2012  

    This worked for me – thank you! (CS5)

  • By Alice - 8:42 AM on February 29, 2012  

    I have the same problem with my cs5.1 software and I don’t know how to stop it if it helps i still have cs5 installed on my computer.

    Please Help

  • By Nic Cohen - 2:28 AM on July 30, 2012  

    This worked wonders, thank you!

  • By Nic Cohen - 2:40 AM on July 30, 2012  


    Thank you!

  • By Simon Ringsmuth - 7:22 PM on January 25, 2013  

    This same issue is happening to me, on OSX Mountain Lion running FW CS5.1. I have tried deleting the preferences as stated, but it still won’t open.

  • By Bmeehan - 6:03 PM on February 18, 2013  

    This works!!! Thanks!!

  • By Haea - 3:49 PM on August 8, 2013  

    Works great