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

johnlerrington1
johnlerrington1
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I've already scanned the old threads with no progress so lets try again. I have a few tabs open on ff. Its working fine, it has NOT crashed. I can copy a link from an email in thunderbird and paste it into ff and a new tab will open to that page. I can click a link in a document and the tab & page will open.

However if I just click the link in thunderbird - hey presto "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window."

It seems TB is not handling the link properly (it always used to!) However the various TB "fixes" I can find are either inscrutable, wrong or just dont work.

Has anyone fixed this?

I've already scanned the old threads with no progress so lets try again. I have a few tabs open on ff. Its working fine, it has NOT crashed. I can copy a link from an email in thunderbird and paste it into ff and a new tab will open to that page. I can click a link in a document and the tab & page will open. However if I just click the link in thunderbird - hey presto "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." It seems TB is not handling the link properly (it always used to!) However the various TB "fixes" I can find are either inscrutable, wrong or just dont work. Has anyone fixed this?

All Replies (2)

FredMcD
FredMcD
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https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding

https://www.basezap.com/cant-open-firefox-because-a-copy-of-firefox-is-already-open-mac/

https://apple.stackexchange.com/questions/196771/cant-open-firefox-because-a-copy-of-firefox-is-already-open

http://kb.mozillazine.org/Firefox.exe_always_open

johnlerrington1
johnlerrington1 Question owner
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Thanks for trying Fred - the problem arises under windows 10. Yes I can close firefox, (without even using task manger) and if I click the link when its closed it launches the link page in ff. So I'd already viewed the links for the problem under windows, and they were no help. Probably I should repost this as a thunderbird issue.