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Firefox not opening after Windows 10 Security Update

  • 1 reply
  • 1 has this problem
  • 21 views
  • Last reply by alexestein

alexestein
alexestein
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I downloaded a Windows 10 update last night. It was Security Intelligence Update for Microsoft Defender Antivirus - KB2267202 (Version 1.361.793.0). Now, I cannot open Firefox. When I click on Firefox for around half a second I see an error box that says "Open Firefox in troubleshooting mode?" and nothing else, with no option to click yes, then the box closes. The same thing happens when I try to run firefox.exe -p to change profiles. I also cannot open Tor Browser, and I am wondering if there is a connection. I have tried uninstalling Firefox using the uninstall tool and reinstalling but I have the same issue. I uninstalled the windows update and opened Firefox. This time, it had the "Open Firefox in troubleshooting mode?" box but I could actually click on the yes option, and Firefox opened. However, when I clicked on the option to get a fresh install and remove the extensions, Firefox closed and I am back to the same place of it not being able to open again.

I downloaded a Windows 10 update last night. It was Security Intelligence Update for Microsoft Defender Antivirus - KB2267202 (Version 1.361.793.0). Now, I cannot open Firefox. When I click on Firefox for around half a second I see an error box that says "Open Firefox in troubleshooting mode?" and nothing else, with no option to click yes, then the box closes. The same thing happens when I try to run firefox.exe -p to change profiles. I also cannot open Tor Browser, and I am wondering if there is a connection. I have tried uninstalling Firefox using the uninstall tool and reinstalling but I have the same issue. I uninstalled the windows update and opened Firefox. This time, it had the "Open Firefox in troubleshooting mode?" box but I could actually click on the yes option, and Firefox opened. However, when I clicked on the option to get a fresh install and remove the extensions, Firefox closed and I am back to the same place of it not being able to open again.

All Replies (1)

alexestein
alexestein Question owner
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I deleted the folder before I uninstalled the update, though I am not sure if I deleted everything I needed to as I am not good with windows. I managed to circumvent the issue by creating a new user account and opening the Firefox download, so maybe it as an issue with parental controls.