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MOZGLUE.DLL - Why missing on desktop only?

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I do not use this desktop for internet access. But when I try to open files that were created on the net some time ago, i get the Missing MOZGLUE.DLL error message. Do some versions of Firefox not contain this file? How is the problem corrected?

I do not use this desktop for internet access. But when I try to open files that were created on the net some time ago, i get the Missing MOZGLUE.DLL error message. Do some versions of Firefox not contain this file? How is the problem corrected?

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What do you mean by:

when I try to open files that were created on the net some time ago

Are these old web pages still on websites, or are they saved files on your computer?

Anyway, all Firefox program files should be complete, so if you get that message often, you may want to:

Clean Reinstall

We use this name, but it's not about removing your settings, it's about making sure the program files are clean (no inconsistent or alien code files). As described below, this process does not disturb your existing settings. Do NOT uninstall Firefox, that's not needed.

It only takes a few minutes.

(A) Download a fresh installer for Firefox to a convenient location. You can choose between:

Regular version for Windows 7-10 https://www.mozilla.org/firefox/all/ Note: only runs Flash, no other legacy plugins "Windows" version is standard 32-bit version you currently run; if you are thinking of switching to the 64-bit version, see: How to switch from 32-bit to 64-bit Firefox

Extended Support Release for Windows XP-10 https://www.mozilla.org/firefox/organizations/all/ Note: Windows (32-bit) runs legacy plugins that ran in Firefox 51; 64-bit runs Flash and Silverlight; if you are thinking of switching to the 64-bit version, see: How to switch from 32-bit to 64-bit Firefox

(B) Exit out of Firefox (if applicable).

(C) Using Windows Explorer/My Computer, rename the program folder as follows:

64-bit Windows users with 32-bit Firefox: Rename

C:\Program Files (x86)\Mozilla Firefox

to

C:\Program Files (x86)\OldFirefox

Other Windows configurations: Rename

C:\Program Files\Mozilla Firefox

to

C:\Program Files\OldFirefox

(D) Run the installer you downloaded in step (A). It should automatically connect to your existing settings.

Note: Some plugins may exist only in that OldFirefox folder. If something essential is missing, look in these folders:

  • \OldFirefox\Plugins
  • \OldFirefox\browser\plugins

Any improvement?