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Cannot launch Firefox after installing but firefox.exe appears in Windows Task Manager

  • 2 replies
  • 3 have this problem
  • 15 views
  • Last reply by cor-el

Rachel Z
Rachel Z
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I recently got a new computer and I am having a problem installing Firefox. In the installation wizard, the last step gives the option to launch Firefox after you click finish, but no window opens. I click on the shortcuts, navigate to the .exe file, use Window's Run tool and nothing will launch Firefox. I am also unable to launch Firefox Profiles Manager using Windows Run tool.

Each time I click the Firefox shortcut, another instance of firefox.exe appears in my Windows Task Manager under Processes. I have uninstalled Firefox (including removing the profile folders/all personal data), but the same issue occurs when I install Firefox the next time.

This is a brand new computer running Windows XP, Service Pack 3 (I am unable to use Windows 7 due to work application compatibility constraints). When I first turned it on this morning, I was able to install and run Firefox. I loaded my profile using Firefox Sync from my old computer to my new computer. Everything was running perfectly, I could pull up the tabs from Old Comp onto New Comp. All my passwords and bookmarks transferred.

Everything fell apart after I installed an Adobe Flash plugin required for one of my bookmarked pages. The Flash installation required me to close Mozilla, and it has never re-opened since. I have uninstalled all the Adobe flash plug-ins I can find using the Add/Remove Programs tool. I have restarted the computer several times, uninstalled and re-installed Mozilla, and tried everything else I can think to do.

What could be prevent Firefox from launching at this point? What should I try next, short of reformatting the entire computer and reinstalling Windows?

I recently got a new computer and I am having a problem installing Firefox. In the installation wizard, the last step gives the option to launch Firefox after you click finish, but no window opens. I click on the shortcuts, navigate to the .exe file, use Window's Run tool and nothing will launch Firefox. I am also unable to launch Firefox Profiles Manager using Windows Run tool. Each time I click the Firefox shortcut, another instance of firefox.exe appears in my Windows Task Manager under Processes. I have uninstalled Firefox (including removing the profile folders/all personal data), but the same issue occurs when I install Firefox the next time. This is a brand new computer running Windows XP, Service Pack 3 (I am unable to use Windows 7 due to work application compatibility constraints). When I first turned it on this morning, I was able to install and run Firefox. I loaded my profile using Firefox Sync from my old computer to my new computer. Everything was running perfectly, I could pull up the tabs from Old Comp onto New Comp. All my passwords and bookmarks transferred. Everything fell apart after I installed an Adobe Flash plugin required for one of my bookmarked pages. The Flash installation required me to close Mozilla, and it has never re-opened since. I have uninstalled all the Adobe flash plug-ins I can find using the Add/Remove Programs tool. I have restarted the computer several times, uninstalled and re-installed Mozilla, and tried everything else I can think to do. What could be prevent Firefox from launching at this point? What should I try next, short of reformatting the entire computer and reinstalling Windows?

All Replies (2)

Rachel Z
Rachel Z Question owner
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I have tried installing an older version (Mozilla 12.0) and still have no ability to open/launch Firefox after installation completes.

This is so frustrating!

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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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:

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance/Themes).

You can try to reset Firefox and create a new profile.