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"class not registered"

  • 22 réponses
  • 92 ont ce problème
  • 17 vues
  • Dernière réponse par cor-el

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there is already another question with the same problem I am having, but to be able comment on it I needed to ask my own question to register. I am running windows 8. I was using firefox when the prompt came up "firefox needs to update... and will reopen in a few moments". Firefox never reopened Instead I received an error message "C:\Program Files (x86)\Mozilla Firefox class not registered". I have uninstalled, reinstalled, deleted C:\Program Files (x86)\Mozilla Firefox , reinstalled and still receive the same error message "C:\Program Files (x86)\Mozilla Firefox class not registered". When I reinstall firefox it never opens its always comes up with the error message. Any solutions?

there is already another question with the same problem I am having, but to be able comment on it I needed to ask my own question to register. I am running windows 8. I was using firefox when the prompt came up "firefox needs to update... and will reopen in a few moments". Firefox never reopened Instead I received an error message "C:\Program Files (x86)\Mozilla Firefox class not registered". I have uninstalled, reinstalled, deleted C:\Program Files (x86)\Mozilla Firefox , reinstalled and still receive the same error message "C:\Program Files (x86)\Mozilla Firefox class not registered". When I reinstall firefox it never opens its always comes up with the error message. Any solutions?

Toutes les réponses (2)

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I think my lap top has a lot more problems, then the sun has Hot spots!  :/ (not that I am down playing any one's situation, nor want to sound cynical or Condescending). Though many of my issues have been resolved through a LOT of time, tech support and a couple friends and personal researching.

But I get the "Class not Registered" Every time I try to update Windows, (I have Mozilla Firefox 30 and Windows 8.1)!.

Some of the problems were self inflicted by not researching properly, so to say the least I am being extremely cautious I have the same issue with Class not Registered, and looking for to some ideas or hopefully the solution. After I try running a windows update and any updates for my virus scan "Defender" which is what I believe windows 8 and 8.1 uses, I am not sure about Vista or Windows 7 have, I never used them, I went right to 8 through a new lap top.

But if anyone does find or even know an answer please reply as well as anyone else who may just be reading, if someone gets anything that did work for them, Let me know. Due to time I couldn't read through more Forum suggestions or links that may work for Err EXE. "Class Not Registered" :) BUT will return later in day. Maybe anything I found an answer for I can pass on. Buddy

Modifié le par BuddyD54

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If you get a pop-up message asking to update Firefox or plugins then such a message is likely a scam and you should never respond to such an alert to avoid getting infected with malware.

  • Only update Firefox via "Help > About" or by downloading and installing Firefox from the Mozilla server and never via a pop-up or link on a web page.
  • Plugins should only be updated via the plugin itself or by visiting the home page of the plugin.

Do a malware check with several malware scanning programs on the Windows computer. Please scan with all programs because each program detects different malware. All these programs have free versions.


Make sure that you update each program to get the latest version of their databases before doing a scan.

You can also do a check for a rootkit infection with TDSSKiller.

See also:

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