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Why am I getting the "Couldn't load XRE functions", error message?

  • 15 replies
  • 13 have this problem
  • Last reply by bearda

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I built Firefox 11 in Fedora 16 32-bit and made it into a tar.bz2 package using the 'make package' command. It works fine in Fedora 16 32-bit. Then I took that package and untarred it in RHEL 6.1, ran the binary and got the 'Couldn't load XRE functions." error.

I have also compiled FF 11 in RHEL 6.1 32-bit and then untarred the package into Fedora 16 32-bit and got the same error.

I downloaded the FF 11 mozilla release tar.bz2 package and it works fine on both Fedora 16 32-bit and RHEL 6.1 32-bit. What am I not doing that mozilla is doing?

All Replies (15)

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Its Problem with ZoneAlarm Extreme Security then disable Virtualization and reinstall Firefox.

Update your Firefox to 17.0.1

Certain Firefox problems can be solved by performing a Clean reinstall. This means you remove Firefox and any leftover program files and then reinstall Firefox. Please follow these steps one by one:

  1. Download the latest Desktop version of Firefox from and save the setup file to your computer.
  2. After the download finishes, close all Firefox windows (click Exit from the Firefox or File menu) and confirm all upcoming messages.
  3. Now, uninstall Firefox by following the steps mentioned in the Uninstall Firefox article.

IMPORTANT: On Windows, the uninstaller has the option to remove your personal data and settings. Make sure that you do not check this option; otherwise all of your bookmarks, passwords, extensions, user customizations and other Firefox user profile data will be removed from your computer.

After uninstalling Firefox on Windows, delete the "Mozilla Firefox" program folder, located by default in one of these locations:

  • (On 32-bit Windows) C:\Program Files\Mozilla Firefox
  • (On 64-bit Windows) C:\Program Files (x86)\Mozilla Firefox
  1. Go to the Windows Start menu and click on "Computer".
  2. In the Explorer window that opens, double click Local Disk (C:) to open the C:\ drive.
  3. Find the "Program Files (x86)" folder or "Program Files" folder.
    • On 32-bit Windows, double-click the Program Files folder to open it.
    • On 64-bit Windows, you will see a "Program Files (x86)" folder AND a "Program Files" folder. Open the Program Files (x86) folder.
  4. Look for a Mozilla Firefox folder. If you find one, right-click it and select Delete and confirm that you want to move the folder to the Recycle Bin.

Now, go ahead and reinstall Firefox:

  1. Double-click the downloaded installation file and go through the steps of the installation wizard.
  2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

Please report back to see if this helped you!

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Try to ask advice at the MozillaZine Third Party/Unofficial Builds forum:

You need to register on the MozillaZine forum site in order to post at that forum.

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I don't have Zone Alarm and I'm not using Windows. Thank you for your quick reply. I will continue investigating.

Modified by SkateboardingBulldog

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On Fedora 16, I have xulrunner 2 installed. On RHEL 6.1, I have xulrunner 1.9.2 installed. Could these difference in versions be the cause of my binary build not running? Also, the Mozilla release build will run on both systems without this error and with 2 different versions of xulrunner installed, one version on each system, and my build will only work on the system I build it on. Why is that?

Modified by SkateboardingBulldog

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The problem also occurs with a fresh install on Red Hat Enterprise Linux Server release 5.6 (Tikanga) , x86-64. Shell session below.

  • [adam@rock ~]$ echo home=$HOME ; pwd ; ls -al ; md5sum firefox-18.0.tar.bz2 ; bunzip2 -c firefox-18.0.tar.bz2 | tar -xf - ; file /work/adam/firefox/firefox
  • home=/work/adam
  • /work/adam
  • total 22152
  • drwxr-xr-x 2 adam users 4096 Jan 10 08:34 .
  • drwxrwxrwx 11 root root 4096 Jan 10 08:20 ..
  • -rw-rw---- 1 adam users 22642722 Jan 10 08:15 firefox-18.0.tar.bz2
  • lrwxrwxrwx 1 adam users 29 Sep 20 10:58 .Xauthority -> /shares/home/adam/.Xauthority
  • 9c13ac73e02f8b0de02871e782e1f52d firefox-18.0.tar.bz2
  • /work/adam/firefox/firefox: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), for GNU/Linux 2.6.18, dynamically linked (uses shared libs), for GNU/Linux 2.6.18, stripped
  • [adam@rock ~]$
  • [adam@rock ~]$ ls -al
  • total 22156
  • drwxr-xr-x 3 adam users 4096 Jan 10 08:35 .
  • drwxrwxrwx 11 root root 4096 Jan 10 08:20 ..
  • drwxr-xr-x 11 adam users 4096 Jan 4 19:44 firefox
  • -rw-rw---- 1 adam users 22642722 Jan 10 08:15 firefox-18.0.tar.bz2
  • lrwxrwxrwx 1 adam users 29 Sep 20 10:58 .Xauthority -> /shares/home/adam/.Xauthority
  • [adam@rock ~]$ /work/adam/firefox/firefox
  • Couldn't load XRE functions.

Modified by 9iB1N

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Same problem here in RHEL 5.8, x86-64.

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I asked a developer and he said to try:
| make -C objdir/toolkit/library clean && make -C objdir/toolkit/library |

Let me know if that helps.

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I'm using the binary I pulled out of the firefox distribution, so I don't think it's a build problem.

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bearda, could you try using a binary from older Firefox nightly builds until you find a nightly build where this error does not appear? We call that regression hunting. Once we find the last good nightly build where the error did not occur, it greatly helps narrow down which bug fix may have caused this error.

There's a archive of nightlies you can check:

Most likely this broke some time in early 2012 or fall 2011. Since the poster of this thread said the same problem happened with Firefox 11 (released March 13 2012).

Download a few mozilla-central builds (which are the nightly builds) and try building with the binaries from those.

The ones you want are in folders in this style:
*date*-random numbers-mozilla-central


Then download the package.

You can skip around to any day in each month. For example, when I'm searching for a regression, I'll download 3 builds per each month. One from the 1st of the month, one from the 15th of the month and another from the end of the month.

Or maybe you're missing a library or package Firefox needs to run?

From the bottom of this page:

Firefox will not run at all without the following libraries or packages:

   GTK+ 2.18 or higher
   GLib 2.22 or higher
   Pango 1.14 or higher
   X.Org 1.0 or higher (1.7 or higher is recommended)
   libstdc++ 4.3 or higher

Modified by NoahSUMO

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I'm not bearda, but here is what you are looking for. Per the immediately prior poster, it would appear that a out of the box redhat 5 installation is no longer sufficient. (That's fine, I'll be upgrading to redhat six sometime during the next six months.).

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Thanks 9iB1N! Nice work. Seems you narrowed it down to in-between 9/19/12 (good) & 9/21/12 (broken). I know it seems obvious but to confirm 9/20/12's build is responsible, could you download that one as well and test it? Thanks.

9/20/12 linux nightly build:

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The 9/20/12 build works (pass).

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Make sure that you meet the system requirements for the current Firefox version, especially the GLib 2.22 or higher library.

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Thanks, Redhat 5.6 has glib2 version 2.12.3 which is older than required. I'll have to await corporate IT to upgrade/update the OS in order to use the new firefox, which probably won't happen soon.

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Strangely enough the GLib requirement was changed with Firefox 17, which still ran under RHEL/CentOS 5. Time to switch to ESR, I guess. I'm curious to see what happens in about a year when ESR 17 goes EOL but RedHat continues to support RHEL 5.