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I am trying to upgrad to version 54. Get error message saying that mozglue.dll is missing after upgra. Do not have avg

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  • Last reply by cor-el

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I am trying to upgrade to version 54. After processing the upgrade, I get an error message saying "the program can't start because mozglue.dll is missing from your computer. Try reinstalling the program to fix this problem."

I have reinstalled the upgrade, renamed all the folder to OLD Mozilla Firefox (twice) and reinstalled the full download (twice) and it still gives me that error message. I do not have AVG on my computer. I am running Windows 7 Home Premium. How do I get Firefox running again?

Thanks.

I am trying to upgrade to version 54. After processing the upgrade, I get an error message saying "the program can't start because mozglue.dll is missing from your computer. Try reinstalling the program to fix this problem." I have reinstalled the upgrade, renamed all the folder to OLD Mozilla Firefox (twice) and reinstalled the full download (twice) and it still gives me that error message. I do not have AVG on my computer. I am running Windows 7 Home Premium. How do I get Firefox running again? Thanks.

All Replies (4)

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Hello,

Certain Firefox problems can be solved by performing a Clean reinstall. This means you remove your Firefox program files and then reinstall Firefox. This process does not remove your Firefox profile data (such as bookmarks and passwords), since that information is stored in a different location.

To do a clean reinstall of Firefox, please follow these steps: Note: You might want to print these steps or view them in another browser.

  1. Download the latest Desktop version of Firefox from mozilla.org (or choose the download for your operating system and language from this page) and save the setup file to your computer.
  2. After the download finishes, close all Firefox windows (or open the Firefox menu New Fx Menu and click the close button Close 29).
  3. Delete the Firefox installation folder, which is located in one of these locations, by default:
    • Windows:
      • C:\Program Files\Mozilla Firefox
      • C:\Program Files (x86)\Mozilla Firefox
    • Mac: Delete Firefox from the Applications folder.
    • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
  4. 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.

More information about reinstalling Firefox can be found here.

WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.

Please report back to say if this helped you!

Thank you.

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Thank you for your reply. I did what you said and got the same error message.

Someone who had the same problem posted back in April 2017 that they found the mozglue.dll file and manually put it in win / sys32 then rebooted their system and it worked. How do I do that? Where can I find the mozglue.dll file?

See post here: http://forums.mozillazine.org/viewtopic.php?f=38&t=3029630

Thank you.

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I fixed it, thanks.

I found a previous version 53.0.3 and downloaded it, deleted the old (new) files and then installed the previous version. Have opened it and it runs.

Thank you for your help.

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Did you delete the Firefox program folder before installing a freshly downloaded Firefox version?

The mozglue.dll file should be in the Firefox installation folder. If it isn't there then it is possible that some security or cleanup software has removed it.

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen or hold down the Shift key) to see if that allows to install Firefox properly.