Firefox is already running but is not responding error message
Hi. This message "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." is recurrent. It happened before, I don't remember exactly when, then stopped when a new version was installed. With the last version of Firefox, it returned. I tried all the suggestions available, namely the one in "support.mozilla.org", but with no success. I guess that this is related with something related with the new version, but it is only a guess. I have a laptop running Win 10, with a single installation. This error occurs essentially when I try to open links from Thunderbird (version, 68.9.0), but there are exceptions. A very few links open in Firefox without the error message. Any suggestions how to fix this issue? Thanks in advance.
All Replies (2)
https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster
https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix
https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram
https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding
https://support.mozilla.org/en-US/kb/firefox-takes-long-time-start-up
https://support.mozilla.org/en-US/kb/quick-fixes-if-your-firefox-slows-down
MemTest LAST UPDATED : 27/09/2013
Could you please run a tool from http://memtest.org/
in order to check the integrity of your RAM?
You will need a thumb or disk drive to install it on.
Do you let Windows handle the page file or did you set a fixed size ?
If you use a fixed size for the page file then try the former and let Windows handle the page file.
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
Do you get this message when you try to open a link in Firefox via an external application?
Check the target field in the Firefox desktop shortcut and make sure you do not start Firefox with the -no-remote switch or have set the environment variable MOZ_NO_REMOTE present
- Control Panel -> System -> Advanced -> Environment variables
If you have a MOZ_NO_REMOTE environment variable then remove this variable and do not change its value to 0 because that doesn't work (Firefox checks for its existence and not the value).