I changed Java settings and now Firefox crashes as it opens, even in safe mode; how can I fix this?
I was trying to change settings to access the comments section of Slate.com. Right or wrong, I changed a Java setting from -1 to 2. The setting was in about:config and I believe it involved some sort of max. As I cannot open anything, I am not sure.
When I made the change, firefox crashed immediately, Every time I have tried to reopen, even in safe mode, it immediately crashes again and will not reopen.
Chosen solution
Hi pternagy, Sorry you are having problems.
For future reference. Those of us that mess directly with about:config soon learn how to recover from mistakes and what it is sensible to backup. Occasionally backing up your entire profile for instance can be useful and would have probably given you a quick solution of copying over the file from that backup.
Ok on to the subject of trying to get Firefox back as it was: Find your profile and the file prefs.js and rename that. (The renamed file is a potentially useful backup.) Firefox is then forced to regenerate the file and will reset your preferences to the default. You can then re open and use Firefox. Next try to get it back to normal.
Trying to manually edit the file prefs.js is normally a bad idea. However if it is a single pref change it may be possible to directly edit the prefs.js file (whilst Firefox is closed) to get everything back to how it was before . You have the renamed file to work with. Probably best to test all this out in a new additional profile then you only break additional test profiles not working profiles essential to Firefox.
These articles should help you:
- http://kb.mozillazine.org/Prefs.js_file
- Reset Firefox preferences to troubleshoot and fix problems_solution-2-delete-firefox-preference-files
- Profiles - Where Firefox stores your bookmarks, passwords and other user data#w_finding-your-profile-without-opening-firefox
- http://kb.mozillazine.org/Using_multiple_profiles_-_Firefox
Please post back with how you get on and whether you need any extra help. Good Luck.
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Chosen Solution
Hi pternagy, Sorry you are having problems.
For future reference. Those of us that mess directly with about:config soon learn how to recover from mistakes and what it is sensible to backup. Occasionally backing up your entire profile for instance can be useful and would have probably given you a quick solution of copying over the file from that backup.
Ok on to the subject of trying to get Firefox back as it was: Find your profile and the file prefs.js and rename that. (The renamed file is a potentially useful backup.) Firefox is then forced to regenerate the file and will reset your preferences to the default. You can then re open and use Firefox. Next try to get it back to normal.
Trying to manually edit the file prefs.js is normally a bad idea. However if it is a single pref change it may be possible to directly edit the prefs.js file (whilst Firefox is closed) to get everything back to how it was before . You have the renamed file to work with. Probably best to test all this out in a new additional profile then you only break additional test profiles not working profiles essential to Firefox.
These articles should help you:
- http://kb.mozillazine.org/Prefs.js_file
- Reset Firefox preferences to troubleshoot and fix problems_solution-2-delete-firefox-preference-files
- Profiles - Where Firefox stores your bookmarks, passwords and other user data#w_finding-your-profile-without-opening-firefox
- http://kb.mozillazine.org/Using_multiple_profiles_-_Firefox
Please post back with how you get on and whether you need any extra help. Good Luck.
Thanks. That helped a lot.
As I suspected, it was the change in Java setting.s
You’re welcome. Thanks for posting back. Glad it is working again.