Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

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
Echekwara usoro a. Biko jụọ ajụjụ ọhụrụ ma ọ bụrụ na ị chọrọ enyemaka.
Echekwara

I always get the message "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." on terying to run firefox

Firefox
cor-el replied Afọ 15 gara aga
MattWhite
MattWhite

When I try to run Firefox I get the message "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."

No copy of firefox is running as far as I can tell. Restart and restoring system to 10 days ago did not help.

Uninstalling and downloading a new copy - but to not avail.

When I try to run Firefox I get the message "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." No copy of firefox is running as far as I can tell. Restart and restoring system to 10 days ago did not help. Uninstalling and downloading a new copy - but to not avail.

All Replies (1)

cor-el
cor-el
  • Onye nduzi

See:

Do you still have a default profile?
If not then delete the file profiles.ini to make Firefox create a new default profile.

  • C:\Documents and Settings\<user>\Application Data\Mozilla\Firefox\Profiles\<profile>\