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Cannot open multiple tabs/windows from apps e.g. Thunderbird

Bob's Firefox
Bob's Firefox
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When I click on a web link in another application (e.g. Thunderbird, or any other application), it opens the webpage in Firefox (fine). Clicking another link produces the message "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." If I click cancel, no new window or tab opens. If I click close firefox, the new link opens in a new tab and the previous tab shows "about:sessionrestore," which allows me to restore windows and tabs ("Well, this is embarrassing") in new windows. This can be repeated, at least for a while, resulting ultimately in lots of windows with a lot of effort to open each one. I have restarted Firefox without add-ons, and also done a full Refresh, without avail. Other computers do not show this problem, even the same model (Dell Optiplex 9010 with Windows 7 Pro x64 and 8 GB RAM). And neither do other browsers (IE11, Chrome), when they are set as default browser. They all permit opening multiple tabs to display multiple webpages from multiple links, which is often important in emails containing multiple links.

When I click on a web link in another application (e.g. Thunderbird, or any other application), it opens the webpage in Firefox (fine). Clicking another link produces the message "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." If I click cancel, no new window or tab opens. If I click close firefox, the new link opens in a new tab and the previous tab shows "about:sessionrestore," which allows me to restore windows and tabs ("Well, this is embarrassing") in new windows. This can be repeated, at least for a while, resulting ultimately in lots of windows with a lot of effort to open each one. I have restarted Firefox without add-ons, and also done a full Refresh, without avail. Other computers do not show this problem, even the same model (Dell Optiplex 9010 with Windows 7 Pro x64 and 8 GB RAM). And neither do other browsers (IE11, Chrome), when they are set as default browser. They all permit opening multiple tabs to display multiple webpages from multiple links, which is often important in emails containing multiple links.

All Replies (2)

guigs
guigs
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I understand that when you click a link from another application that it tries to open up another instance of Firefox. I am happy to help.

  1. Open your Profile folder Profiles - Where Firefox stores your bookmarks, passwords and other user data
  2. Search for a "lock" file or a "parent.lock" file, delete it and restart Firefox.

Does this still happen?

Bob's Firefox
Bob's Firefox Question owner
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parent.lock is always present in my profile folder. I had already tried playing around with this. If you delete it, a new file is produced whenever firefox is opened, and it stays there, even after the browser is closed. Once firefox is open, the file cannot be deleted (it is "in use"). I had already tried writing something to this file (it is normally empty), making it read only, etc etc., while firefox was closed. Nothing worked. I doubt this file causes the problem, since it does not prevent firefox from opening in the first place, and it is present on other computers not showing this problem. The problem is that once firefox is opened (either directly or from a link), trying to open another link in a new tab fails -- as explained on line 3 above.