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After an upgrade, I can no longer open Firefox

Posted

A routine upgrade offer came through this morning and I accepted and continued working on my PC. Later, I could not open Firefox by using Desktop or Programmes. I rebooted my PC with the same results. I thought of uninstalling and reinstalling but thought that maybe someone could offer a quick fix.

Chosen solution

A possible cause is security software (firewall,anti-virus) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.

See:

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Additional System Details

Application

  • User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; BTRS31753; SearchToolbar 1.2; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET4.0C; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)

More Information

Tyler Downer
  • Administrator
  • Moderator
1165 solutions 6642 answers

Does Firefox Crash? Have you scanned for malware? Firefox 18 crashes on startup due to malware - how to fix? Do you have websense endpoint on your computer?

Question owner

No, it doesn't crash, it doesn't even open. Clicking the icon on the desktop, or Start, Programmes, Firefox gets no respose at all. Even clicking on the email link has no effect, as Firefox is my defaut browser. I have Kaspersky antivirus/Internet protection running all the time, so I presume I have been protected against malware. I do not know what websense endpoint is, so I doubt if it is on my PC. Would welcome any further suggestions. Thanks, Mike

Tyler Downer
  • Administrator
  • Moderator
1165 solutions 6642 answers

Helpful Reply

Please run the malware programs I suggested, then try to reinstall Firefox.

cor-el
  • Top 10 Contributor
  • Moderator
10762 solutions 96861 answers

Chosen Solution

A possible cause is security software (firewall,anti-virus) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.

See:

Question owner

No Malware detected. Uninstalled and reinstalled and it works perfectly. Thanks.