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Cannot Open Firefox Browser

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  • 0 leis an bhfadhb seo
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  • Freagra is déanaí ó lfwood2

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Yesterday I left work and my computer on with several Firefox tabs open. Today I came in and Firefox was closed. Double clicking the icon on my desktop, or on the icon in the taskbar gives the small circle loading symbol next to the mouse for about a second. But no browser window opens. There is no indication in the Task Manager that a Firefox browser is open.

I have attempted to restart my computer several times. I have uninstalled and reinstalled Firefox. I have tried updating Firefox. I have checked that all my drivers on the computer are up to date. I have run a Malwarebytes virus scan on my computer. I cannot get Firefox to open to check any other settings. I have tried to open Firefox on another account on the same computer and it also results in the same thing.

If anyone has any ideas that might fix this, I would really appreciate it. Thank you. Computer is a Dell OptiPlex 5070 running Windows 10.

Yesterday I left work and my computer on with several Firefox tabs open. Today I came in and Firefox was closed. Double clicking the icon on my desktop, or on the icon in the taskbar gives the small circle loading symbol next to the mouse for about a second. But no browser window opens. There is no indication in the Task Manager that a Firefox browser is open. I have attempted to restart my computer several times. I have uninstalled and reinstalled Firefox. I have tried updating Firefox. I have checked that all my drivers on the computer are up to date. I have run a Malwarebytes virus scan on my computer. I cannot get Firefox to open to check any other settings. I have tried to open Firefox on another account on the same computer and it also results in the same thing. If anyone has any ideas that might fix this, I would really appreciate it. Thank you. Computer is a Dell OptiPlex 5070 running Windows 10.

All Replies (4)

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Sorry to hear about this problem. Could you take a look at the following thread and see whether any of the discussion there looks relevant:

https://support.mozilla.org/questions/1407995

In the Windows Task Manager, check the "Details" tab for any instances of firefox.exe that might not yet show on the "Processes" tab.

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Hello, none of that thread really seemed all that relevant except to check AppData>Roaming>Mozilla. I can see I have no extensions in that folder (might be because I just reinstalled? I swear I at least had an adblocker). Nothing in SystemExtensionsDev. In the Firefox folder, the most recent "Date modified" subfolders are in "prefs" and "parent.lock" last night, and the the "Profiles" subfolder, there are some modified .json from last night and .sqlite files from this morning. I don't know if that is at all relevant to solving this.

In the "Details" tab in the Task Manager, if I repeatedly click on my Firefox desktop icon, I can see a number of "firefox.exe" tasks that are trying to start, with updating PID numbers, but they close in about half a second.

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I don't think this is caused by a problem with extensions. The information about the Details tab is interesting, especially if Firefox is trying to restore a number of tabs from a previous session. Firefox will try to create new child processes for each different site and it sounds like "something" is killing them, whether that is the system, security software, or something else. I wish I could tell you what it was.

If you right-click > End Process or End Process Tree on any firefox.exe processes that stick around and don't lose immediately, and then immediately try starting Firefox again, does it work any better the second time?

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Hello jscher,

Since was Friday, I just shut down my computer and hoped for a miracle on Monday. Today when I got in, there was, surprise, no change. But in desperation, I just clicked on the Firefox icon on my desktop about a hundred times and it actually opened. There seemed to be about 9 instances of Firefox in the Task Manager, but only one open browser and tab.

Since I now have access to Firefox, I was wondering if there were any troubleshooting methods I should try from Firefox itself. I tried opening "Troubleshoot Mode", but it would not reopen on its own. Attempting to reopen Firefox, just restored my previous session.

I appreciate your help a lot!