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Firefox won't open and neither will Profile Manager.

  • 6 replies
  • 5 have this problem
  • 10 views
  • Last reply by bloodsail22

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I running Windows 7 Professional. So about two weeks ago I had suddenly was unable to open Firefox and since then have been trying to solve it myself to no avail. the Firefox process opens in the task-manager, however, the browser window does not appear. When trying to open Firefox again, another process opens and the same thing happens. Processes just keep opening and that's it. I have tried the Profile manager but it only opened once and I have been unable to get it to open again. Every once in a while Firefox actually opens when I launch it, but when I close it to see if it works again it does not. Firefox does open in Safe-mode with Networking with no problems consecutively. While it was in safe-mode I ran a full system scan with Nortan Antivirus and cleared about thirty threats but after the restart Firefox still won't open, only processes. I have tried deleting Mozilla from the x86 path and cleared My local and roaming Mozilla appdata, then re installed with 34.0.5. I have tried opening Firefox in safe mode but it won't open at all, only the process again.

I running Windows 7 Professional. So about two weeks ago I had suddenly was unable to open Firefox and since then have been trying to solve it myself to no avail. the Firefox process opens in the task-manager, however, the browser window does not appear. When trying to open Firefox again, another process opens and the same thing happens. Processes just keep opening and that's it. I have tried the Profile manager but it only opened once and I have been unable to get it to open again. Every once in a while Firefox actually opens when I launch it, but when I close it to see if it works again it does not. Firefox does open in Safe-mode with Networking with no problems consecutively. While it was in safe-mode I ran a full system scan with Nortan Antivirus and cleared about thirty threats but after the restart Firefox still won't open, only processes. I have tried deleting Mozilla from the x86 path and cleared My local and roaming Mozilla appdata, then re installed with 34.0.5. I have tried opening Firefox in safe mode but it won't open at all, only the process again.

Chosen solution

It is possible that your security software (firewall, anti-virus) 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 install for Firefox and the plugin-container process and the updater process.

See:


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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All Replies (6)

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Did you start the computer in safe mode, or Firefox?


Start Firefox in Safe Mode {web Link} by holding down the <Shift (Mac Options) > key, and then starting Firefox. Is the problem still there?

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FredMcD said

Did you start the computer in safe mode, or Firefox?

Start Firefox in Safe Mode {web Link} by holding down the <Shift (Mac Options) > key, and then starting Firefox. Is the problem still there?

I stated I tried both, Firefox opens with my computer in safe mode but not when I try and open Firefox in safe mode. I just does the same thing, opening as many processes as I try.

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Chosen Solution

It is possible that your security software (firewall, anti-virus) 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 install for Firefox and the plugin-container process and the updater process.

See:


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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cor-el said

It is possible that your security software (firewall, anti-virus) 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 install for Firefox and the plugin-container process and the updater process. See:

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:

My firewall has been off for ages. And I did a check with Nortan. It didn't help.

EDIT: Turns out I was just being lazy I guess. I had read this post before on another user and it didn't work for him so I didn't try it. AWD did clean a lot of stuff but didn't work, Malwarebytes however cleaned more things and suddenly Firefox opens each time I try. Not sure if it is permanent yet.

Modified by bloodsail22

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Virus scans are good, but many can't detect add / mal-ware.

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.

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Update, Firefox works, Firefox safe mode works, and the profile manager works. Thanks for your help.