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I want to open in 32-bit mode


to watch movies in Firefox, I need tobe in 32-bit mode. How do I get there from here?

Additional System Details

Installed Plug-ins

  • Gecko default plugin
  • Runs Java applets using the latest installed versions of Java. For more information: Java Embedding Plugin. Run version test: Java Information.
  • Picasa plugin.
  • http://www.facebook.com/fbplugin/
  • Shockwave Flash 10.2 r159
  • Java Plug-In 2 for NPAPI Browsers
  • 4.0.51204.0
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in web pages. For more information, visit the QuickTime Web site.
  • Microsoft Office for Mac SharePoint Browser Plug-in
  • The Flip4Mac WMV Plugin allows you to view Windows Media content using QuickTime.
  • Version 0.9.16, copyright 1996-2006 The VideoLAN Team, 2006-2009 Veetle, Inc.http://www.veetle.com
  • Version 0.9.16, copyright 2006-2009 Veetle Inchttp://www.veetle.com
  • Version 0.9.16, copyright 2006-2009 Veetle Inc.http://www.veetle.com
  • Used for supporting web links for Hulu Desktop.
  • Adobe Shockwave for Director Netscape plug-in, version 11.5.2
  • Coupons Inc. Plugin
  • MacCinema
  • RealPlayer Plugin
  • Yahoo! Installer Plug-in provides application installation support
  • iPhoto6


  • User Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv: Gecko/20090729 Firefox/3.5.2

More Information

  • Top 10 Contributor
2348 solutions 20818 answers

I don't think Firefox for Mac has a 64-bit mode. The error message could indicate some other incompatibility... do you want to mention the particular web site?


Have you considered installing a later version of Firefox? 3.5.2 is almost two years old now and has some security vulnerabilities.

If you prefer the last 3.5.x, see:

For the last 3.6.x, see:

  • Top 10 Contributor
  • Moderator
10740 solutions 96657 answers

Helpful Reply

On a Mac, Firefox 4 is a 64 bit application.
Not all plugins support 64 bit and if not then you need to start Firefox in 32 bit mode to use that plugin.

  1. Close Firefox
  2. Open the Applications folder in Finder
  3. Right click or control-click the Firefox.app icon
  4. Select "Get Info"
  5. Select or Deselect "Open in 32-bit mode"
  6. Close the "Firefox Info" window
  7. Restart Firefox