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Strange issue likely involving Avast-1 of 4 accounts does not run firefox any longer.

  • 13 replies
  • 1 has this problem
  • 1 view
  • Last reply by guentzelnd

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I recently had installed Avast and after a few days, after running a scan on avast, it found and quarantined a "possible threat" string of code from firefox and my steam app. Unwittingly and to be honest, in a small hurry, I removed the quarantined items and went about my business. I have Windows accounts on my computer, 3 users and an admin. 2 users and the Admin can run FF, but the 1 user account cannot. I have tried some of the troubleshooting steps to create a new profile and have uninstalled the whole mozilla app. I really like the browser and am not having any luck getting FF to work on the one account. I have since uninstalled Avast and have UN and Re installed FF along with trying to create a new profile for my afflicted user account. No luck. When I click the FF app to start it, I get a white flash box, but too quick to read. Also, When I perform a run search for firefox.exe, Windows cannot find it, even though it is on my pc. Please help.

I recently had installed Avast and after a few days, after running a scan on avast, it found and quarantined a "possible threat" string of code from firefox and my steam app. Unwittingly and to be honest, in a small hurry, I removed the quarantined items and went about my business. I have Windows accounts on my computer, 3 users and an admin. 2 users and the Admin can run FF, but the 1 user account cannot. I have tried some of the troubleshooting steps to create a new profile and have uninstalled the whole mozilla app. I really like the browser and am not having any luck getting FF to work on the one account. I have since uninstalled Avast and have UN and Re installed FF along with trying to create a new profile for my afflicted user account. No luck. When I click the FF app to start it, I get a white flash box, but too quick to read. Also, When I perform a run search for firefox.exe, Windows cannot find it, even though it is on my pc. Please help.

All Replies (13)

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About that one user, Please explain the problem in detail. What happens? What is/are the exact error message(s) ?

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Video of Desktop in action

This is the best I can do. I can't open the application on this user account. It flashes a box like the browser is trying to open. There is no error message. I would really like to find out what is the problem. How best can I assist?

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I don't know if this is your problem. But we have been seeing this a lot of late.

You can check for issues caused by a corrupted or incomplete Visual C++ installation that is missing runtime components (Redistributable Packages) required by Firefox, especially VCRUNTIME140_1.dll.

Install both 32-bit and 64-bit "Visual Studio 2015, 2017 and 2019" downloads, (x86: vc_redist.x86.exe and x64: vc_redist.x64.exe) from https://support.microsoft.com/help/2977003/the-latest-supported-visual-c-downloads

You may not need the latter (32-bit version) if you use 64-bit Firefox. You may have to reboot the computer. ++++++++++++++++++++++++++++++++++++++++++++++ In another thread, a user reported that a recent update of Malwarebytes Anti-Exploit (version 415) may be causing symptoms similar to the VC Runtime problem. If you have MBAE, it should have a setting to exempt Firefox. You could test whether that makes any difference.

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FredMcD, thanks for your assistance. I downloaded the 64 bit version and ran the update and restarted the computer. Once restarted, all windows user accounts can open and run FF! Thanks for your time and assistance. I appreciate it.

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Glad to help. Safe Surfing.

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Fred, Actually, just noticed this and did not check before. After closing the browser or logging off user, the firefox app won't open. Even after installing the download previously.

The only work around I have found is trying to reinstall the patch repeatedly. What gives?

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First: A post was flagged as Solved Problem. If the problem is not solved, please remove that flag. If you don’t, others that can help may not read this post.

Go to that message, and use the Undo link to its right.


I will call for more help.

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Thanks Fred. So, the installation of the visual studio will temporarily fix the issue and allow me to use FF, however, sometimes the browser will close on me and other times it just won't open period.

I think this may be somewhat related, however, I am wondering if the user profile in FF has anything to do with the issue? Anyway, I appreciate your help and time and await further instruction on this problem.

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guentzelnd said

I am wondering if the user profile in FF has anything to do with the issue?

Use these links to create a new profile. Use this new profile as is. Is the problem still there?

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

http://kb.mozillazine.org/Profile_folder_-_Firefox#Navigating_to_the_profile_folder

https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles


Type about:profiles<enter> in the address box.

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I cannot access FF from the "problem profile user account". The only error message I receive is that FF is not installed! Which is odd, because I am on a different windows user account right now with FF.

I am not sure what to do and am a bit frustrated.

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I called for more help.

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Thanks for the reply Fred. I will wait for a contact. Much appreciated.

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Waiting on that call for help. So far I have uninstalled and completely removed firefox from my computer and still cannot open the app on this specific profile.

What is the problem? Likely a profile issue, as 3 others work.

At one point the visual studio temporarily worked.

pretty frustrated.