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Firefox Script Error and Plugin Not Updating, Keeps Freezing - Can't Use

  • 9 replies
  • 5 have this problem
  • 14 views
  • Last reply by mattcamp

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Hi, I just starting getting this problem since Thursday.

Windows 10 Home 64 bit Checked all windows and other updates. Firefox is the latest version 55.0.2, tried many basic steps and what i could find online.

1) Script error pops up when i open the browser. Whether i click on continue or stop, it comes back shortly. I have removed this moz plugin. Firefox freezes.

"moz-extension://8a1c9869-c8d2-…/data/content_script/inject.js:94"

2) On the plugins page, i see that firefox is asking for the second shockwave flash 21.0 to be updated. But it looks like i already have the 26.0 version installed. Anyways, i still tried updating flash many times, closed browsers and restarted but this still says that it is outdated. Not sure if this is the issue.


Please help me fix this issue as i cannot use firefox. I do like this brower and want to use it again.

Image attached.


Thank you.

Hi, I just starting getting this problem since Thursday. Windows 10 Home 64 bit Checked all windows and other updates. Firefox is the latest version 55.0.2, tried many basic steps and what i could find online. 1) Script error pops up when i open the browser. Whether i click on continue or stop, it comes back shortly. I have removed this moz plugin. Firefox freezes. "moz-extension://8a1c9869-c8d2-…/data/content_script/inject.js:94" 2) On the plugins page, i see that firefox is asking for the second shockwave flash 21.0 to be updated. But it looks like i already have the 26.0 version installed. Anyways, i still tried updating flash many times, closed browsers and restarted but this still says that it is outdated. Not sure if this is the issue. Please help me fix this issue as i cannot use firefox. I do like this brower and want to use it again. Image attached. Thank you.
Attached screenshots

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Good, glad you solved.

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The Refresh feature (called "Reset" in older Firefox versions) can fix many issues by restoring Firefox to its factory default state while saving your bookmarks, history, passwords, cookies, and other essential information.

Note: When you use this feature, you will lose any extensions, toolbar customizations, and some preferences. See the Refresh Firefox - reset add-ons and settings article for more information.

To Refresh Firefox:

  1. Open the Troubleshooting Information page using one of these methods:
    • Click the menu button New Fx Menu, click help Help-29 and select Troubleshooting Information. A new tab containing your troubleshooting information should open.
    • If you're unable to access the Help menu, type about:support in your address bar to bring up the Troubleshooting Information page.
  2. At the top right corner of the page, you should see a button that says "Refresh Firefox" ("Reset Firefox" in older Firefox versions). Click on it.
  3. Firefox will close. After the refresh process is completed, Firefox will show a window with the information that is imported.
  4. Click Finish and Firefox will reopen.

Did this fix the problem? Please report back to us!

Thank you.

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For the moz-extension...inject.js error, I think that came up in another thread but I don't remember which extension causes it. If you Refresh, that will remove your extensions, but if you don't want to do that just yet:

You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

  • Ctrl+Shift+a (Mac: Command+Shift+a)
  • "3-bar" menu button (or Tools menu) > Add-ons
  • type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions. Then cast a critical eye over the list on the right side. Any extensions that Firefox installs on its own are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything suspicious? If in doubt, disable.

Often a link will appear above at least one disabled extension to restart Firefox before the change takes effect. You can complete your work on the tab and click one of the links as the last step.

Any improvement?


Regarding Flash, Adobe offers an uninstaller to clear all Flash from the computer, and then you can reinstall just the latest version. I think the links are here:

Flash Plugin - Keep it up to date and troubleshoot problems

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Was painfully slow......

Did the refresh.

the shockwave flash still says outdated. Should i just ignore this?

haven't seem the script popup at least yet.

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You might want to update it, but it's totally up to you.

Did the refresh solve your problem?

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I think so atm. havent seen the script pop up.

But i cannot update this shockwave flash 21.0. I have installed it five times now. Restarted browser and computer but it still says this needs to be updated.

But the second plugin is shockwave flash 26.0 so i think this is just an error.

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OK, this is good news.

I am glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution more easily.

Thank you for contacting Mozilla Support.

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If Firefox tries to run Flash 21 in preference to Flash 26 you may not be able to use Flash when the old version becomes permanently blocked.

Official Solution: Run Adobe's uninstaller to scrub all Flash off the system, then reinstall. E.g., Flash Plugin - Keep it up to date and troubleshoot problems.

Unofficial Solution: Find the older DLL file and delete it manually. (There's also usually a registry entry pointing to it, but that's extra work to clean up.)

If you want to try the unofficial approach, type or paste about:plugins in the address bar and press Enter/Return to load it.

This page should list the Flash version 21 plugin somewhere, and also the complete path to the file on disk. With the 32-bit version of Firefox on 64-bit Windows, that's usually this folder:

C:\Windows\SysWOW64\Macromed\Flash

With 64-bit Firefox on 64-bit Windows (or 32-on-32), it's usually here:

C:\Windows\System32\Macromed\Flash

Please be very careful in that folder to delete ONLY the older file identified on the about:plugins page because other files here may be used by Internet Explorer or applications on your system. Anyway, if you remove something important, you can use the Official Solution to clean it all up.

Success?

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Ok finally good now i think.

Uninstalled adobe using the uninstaller and reinstalled the latest version.

Everything seems to be working now.

Thank you guys very much:)

Had to go to ikea to pick up a table, sorry for the delay.

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Chosen Solution

Good, glad you solved.