


[FIXED!] Firefox Is Already Running, but Is Not Responding
Jun 04, 2025 am 12:46 AMFirefox is a widely used web browser. However, this doesn't mean you won't face problems while using it. When Firefox seems to be running but isn't responding, it can be quite frustrating. You might want to open it, but it doesn't appear on the screen. How can you resolve this issue? MiniTool Software will provide you with some effective solutions.
Firefox stores your bookmarks, personal settings, and other information in your Firefox profile. For normal operation, it requires an unlocked profile. If the profile is accidentally locked, you may receive a message saying Firefox is already running, but is not responding. In this article, we will demonstrate how to eliminate this error message and return Firefox to its normal state.
What to Do If Firefox Is Already Running?
- End all Firefox processes in Task Manager
- Restart your computer
- Remove the profile lock file
- Remove the -no-remote startup option
- Initialize the connection to a file share
- Check access rights
- Restore data from a locked profile
Solution 1: End All Firefox Processes in Task Manager
If Firefox wasn't closed properly last time, some Firefox processes may still be running in the background. These running processes are often the cause of the "Firefox is already running" issue. If you see the following interface, you can click the Close Firefox button and then try reopening it to see if it works as expected.
If the above step doesn't work, you can open Task Manager to locate and forcibly terminate these processes.
- Right-click the taskbar and select Task Manager.
- Scroll down to find the Firefox process and end them one by one.
Solution 2: Restart Your Computer
You can also simply restart your computer to address the problem. This ensures your computer runs in a clean environment and terminates all hidden Firefox processes. It can also resolve temporary issues that might cause Firefox to not respond, fail to close, or fail to open.
Solution 3: Remove the Profile Lock File
An abnormal shutdown of Firefox leaves lock files behind. To restore normal functionality, navigate to the profile folder and delete the parent.lock file within it.
- Press Win+R to open Run.
- Enter %APPDATA%\Mozilla\Firefox\Profiles\.
- Press Enter to open the profile folder.
- Locate the folder ending with .default and open it. There should typically be only one folder here, and it should always include a .default folder.
- Find the parent.lock file and delete it.
Solution 4: Remove the -no-remote Startup Option
Command line options can be used to specify certain startup options for Mozilla applications. However, this can sometimes lead to the issue of Firefox being already running but unresponsive.
If you started Firefox with the -no-remote command line option, you can remove this option and then check if you can open Firefox successfully.
Solution 5: Initialize the Connection to a File Share
If your profile files are stored on a file share, you can access the file share via Windows Explorer beforehand to initialize the connection to a file share.
Solution 6: Check Access Rights
Ensure that Firefox has the necessary privileges to create files in the profile folder. If not, you won't be able to open Firefox as usual.
Here are the steps you should take:
- Press Win+R to open Run.
- Enter %APPDATA%\Mozilla\Firefox\Profiles\.
- Press Enter to open the profile folder.
- Right-click the .default folder and select Properties.
- Under General, ensure the Read-only option is unchecked.
Solution 7: Restore Data from a Locked Profile
If none of the previous six methods resolve the issue, you may need to use the Profile Manager to create a new profile and transfer your data from the locked profile to the new one. This post provides useful information: Profile Manager – Create, remove, or switch Firefox profiles.
We hope these methods help you eliminate the "Firefox is already running but is not responding" issue. If you encounter any other problems, feel free to let us know in the comments.
The above is the detailed content of [FIXED!] Firefox Is Already Running, but Is Not Responding. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undress AI Tool
Undress images for free

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

This Gmail login/sign-in guide teaches you how to sign up for a Gmail account, sign in or log in to Gmail, how to sign out of Gmail, etc. on computer, Android, iPhone/iPad.

You can schedule an email when you are not available to send at the desired time or a particular time. Hence, do you know how to schedule an email in Outlook? This post from php.cn will show you a tutorial of Outlook schedule email.

Are you looking for effective solutions to the Steam corrupt update files error? If so, you are at the right place. Here, this post from php.cn introduces how to fix this error in detail. Just keep reading.

What does ASUS Live Update do? How to download ASUS Live Update in Windows 10? How to install/uninstall ASUS Live Update? How to use this utility? After reading this post from php.cn, you should know a lot of information about this tool.

There are many factors that can affect your gaming experience and latency is one of them. What is latency in gaming and how to improve latency on PC? This post on php.cn Website will how you in details.

In this post, you’ll learn how to translate a web page in Google Chrome on desktop or mobile, how to adjust Google translation settings, how to change Chrome language. For more Chrome tips, computer tips, useful computer tools, you can visit php.cn S

Check the simple review of Hotspot Shield VPN and download Hotspot Shield VPN for PC, Chrome, Mac, Android, iOS, etc. to use this VPN service to browse worldwide content.

This post from php.cn Software introduces Microsoft Xbox Game Pass. You can subscribe Xbox Game Pass (Ultimate) service to play over 100 high-quality games on your Windows 11/10 PC. Xbox Game Pass will be built into Windows 11 and brings users a bett
