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firefox will not start. Cannot end process in task manager

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As of this morning, I cannot get Firefox to work. I am using Windows 7. I click to start firefox and it looks like the program starts. It opens a Window with the minimize, maximize, and close buttons but the window contents are blank and the load icon appears. I can minimize and maximize the window but I cannot end the program. If I use CTRL-ALT-DEL, I can see that firefox.exe is running but I cannot end the task by selecting End Process. If I try to start another instance of Firefox, I get a warning box saying "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window."

Nothing I try will end the process.

I uninstalled and re-installed Firefox but the problem persists. I tried doing a fresh install with all previous add-ons and whatnot ignored but it still won't run. I've tried running it with the anti-virus disabled as well as with Windows in Safe Mode but it won't work.

Any ideas?

As of this morning, I cannot get Firefox to work. I am using Windows 7. I click to start firefox and it looks like the program starts. It opens a Window with the minimize, maximize, and close buttons but the window contents are blank and the load icon appears. I can minimize and maximize the window but I cannot end the program. If I use CTRL-ALT-DEL, I can see that firefox.exe is running but I cannot end the task by selecting End Process. If I try to start another instance of Firefox, I get a warning box saying "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." Nothing I try will end the process. I uninstalled and re-installed Firefox but the problem persists. I tried doing a fresh install with all previous add-ons and whatnot ignored but it still won't run. I've tried running it with the anti-virus disabled as well as with Windows in Safe Mode but it won't work. Any ideas?

All Replies (20)

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Hi did a clean install of Firefox 68 and AVG Free and still didn't work. It worked fine to start with but the next day when I restarted my machine it still kept hanging. I hope that helps.

I have now gone back to Friefox 67.0.4 and the problem has gone.

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I can’t. I’m unable to get Firefox to run at all so I cannot access the information. As soon as I install anti-virus, Firefox stops working.

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VeejUK said

I have now gone back to Friefox 67.0.4 and the problem has gone.

Keep after AVG support.

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Still not working for me Vaclav

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Did you try using v67 ?

Install Older Version Of Firefox {web link} Be sure to read everything here.

If you still want to downgrade, look under; I still want to downgrade. Click the Directory of other versions and languages link. Look for the directory of the version that you want. But, remember that old versions may have security issues.

You should also check out Firefox; Extended Support Release {web link} ESR Notes System Requirements

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Hi, may I ask you to download process explorer (https://docs.microsoft.com/en-us/sysinternals/downloads/process-explorer) and create a dump of stuck firefox.exe process ? Right click on the firefox icon in process explorer and from context menu select create dump -> create full dump. Zip all dumps into firefox_got_stuck_your_nick.zip and upload them to avast ftp for analysis (https://support.avast.com/en-eu/article/FTP-file-upload). Thank you for help !

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Thank you vaclav. I uploaded 2 files.

firefox_got_stuck_SDRobot.zip

firefox_got_stuck_SDRobot2.zip

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Where?

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To the Avast FTP site.

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SDRobot thank you for help. Can you try to disable avast components one by one and test if firefox is able to start properly or not. Web shield, File shield, Antirootkit, Behavioral Shield.

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I tried this in AVG free and still didn't start, only thing that would is uninstall AVG completely. hope this helps. I have also created a post in the AVG support

https://support.avg.com/answers#!/feedtype=RECENT_REPLY&dc=All&criteria=UNANSWERED

hopefully someone can help!

Athraithe ag VeejUK ar

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VeejUK have you tried to disable whole av ? In settings -> Core Shields there is green ON checkbox when you uncheck it all shields will be disabled (for example for 10 minutes)

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I’ve tried disabling shields individually as well as disabling all of Avast. Firefox won’t start unless I completely uninstall Avast.

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Firefox 68 uses a new launcher process to restrict DLL injection into the firefox.exe process. It could be that there is a compatibility problem between (some versions of) Avast/AVG and the launcher process design. However, I am not familiar with the details of how Avast/AVG interacts with Firefox at startup.

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SDRobot in dumps you provided us is one avast dll E:\Program Files (x86)\Avast\aswhook.dll. Can you please disable avast self defense in settings and rename this dll it to E:\Program Files (x86)\Avast\aswhook.dll.org and restart firefox. Thank you for help  !

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I tried renaming aswhook.dll. When I try to start Firefox now, I get a blank window that fills the entire screen but Firefox does not start. I cannot close firefox.exe via task manager/end process and I cannot move or minimize the Firefox window so I cannot access my desktop.

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Dear people, as I see names like Avast and AVG mentioned here; for future reference :

You're best off with just using Windows built-in Defender and maybe let malwarebytes run a scan once a month.

Also see :

https://www.howtogeek.com/239950/dont-use-your-antivirus-browser-extensions-they-can-actually-make-you-less-safe/

And :

http://tech.firstpost.com/news-analysis/ex-mozilla-firefox-developer-says-anti-virus-software-does-more-harm-than-good-359798.html

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Has anyone managed to solve the issue? I have reported to AVG support and they are looking into this too. Currently I've gone to using Chrome...sad times!

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currently speaking with AVG support if anyone wants to follow this or respond please see:

https://support.avg.com/answers?id=9060N0000005M4Z

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Hi all thank you for patience, we contacted firefox to help us resolve the issue. Can you restart in safe mode and access about:crashes to get a crash ID ? Thank you

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