This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

I get the following message when trying to open Firefox: "Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system."

  • 2 balasan
  • 2 ada masalah ini
  • 1 paparan
  • Balasan terakhir oleh TonyE

more options

I have tried rebooting the PC and can open Firefox once but if a close and try to reopen, same message pops up. Have also unistalled and reinstalled, to no avail.

I have tried rebooting the PC and can open Firefox once but if a close and try to reopen, same message pops up. Have also unistalled and reinstalled, to no avail.

All Replies (2)

more options
more options

ignore this duplicate post

Diubah oleh TonyE