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.

Avatar for Username

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

This thread was archived. Jei jums reikia pagalbos, užduokite naują klausimą.

A copy of Firefox is already open. Only one copy of Firefox can be open at a time. I GET THIS MESSAGE - BUT FIREFOX APPEARS NOT TO BE OPEN.????????

  • 1 reply
  • 22 have this problem
  • 3 views
  • Paskiausią atsakymą parašė John99

burtrashbaum
burtrashbaum
more options

i have already deleted (trashed) all versions of firefox, and then re-downloaded the new Firefox, and when i try to open it, i get the message, "A copy of Firefox is already open. Only one copy of Firefox can be open at a time."

i have already deleted (trashed) all versions of firefox, and then re-downloaded the new Firefox, and when i try to open it, i get the message, "A copy of Firefox is already open. Only one copy of Firefox can be open at a time."

All Replies (1)

John99
John99
more options

Make sure you allow Firefox a few minutes to close down,and always use the menu options to close Firefox (Not just closing a window or killing the process).

Just for now Look for Firefox processes or plugin container that are still running and kill them before trying again.