We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

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

Error Message When Trying to Open the App

  • 1 பதிலளி
  • 0 இந்த பிரச்னைகள் உள்ளது
  • 1 view
  • Last reply by Toad-Hall

Hello,

I am trying to open the Thuderbird app on my Windows desktop PC, however I keep getting the following error message before the program even opens:

``Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window.``

I have tried closing the background processes using alt, ctrl, delete. I also tried uninstalling, and then reinstalling the Thunderbird app from the setup file. I`ve also tried deleting the setup file, and installing it again fresh from the website.

Every time, the same error message appears and I cannot open it.

How can I solve this problem?

Thank you so much.

Hello, I am trying to open the Thuderbird app on my Windows desktop PC, however I keep getting the following error message before the program even opens: '''``Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window.``''' I have tried closing the background processes using alt, ctrl, delete. I also tried uninstalling, and then reinstalling the Thunderbird app from the setup file. I`ve also tried deleting the setup file, and installing it again fresh from the website. Every time, the same error message appears and I cannot open it. How can I solve this problem? Thank you so much.

All Replies (1)

Maybe it's possible Thunderbird had not completely updated all background processes before computer was shut down, so it still has a setting which the program reads as 'I'm already running'.

Try this:

In bottom search type: %Appdata% - see image below as guide

  • select the %Appdata% file folder
  • select 'Roaming' folder
  • select 'Thunderbird' folder
  • Select 'Profiles' folder
  • select 'the profile name ' folder
  • delete this file : parent.lock

When you Start thunderbird that file will get recreated which is normal.