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What am I supposed to do with a folder named "Old Firefox Data" and I really don't remember what I did to have that backed up?

  • 9 replies
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  • Last reply by AliceWyman

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I'm not sure what I did to cause Firefox to do I GUESS a BACKUP. Since I now have a folder named "Old Firefox Data" what do I do with it? Do I need to somehow re-instate all that is in this folder back into my Firefox Browser? Or, do I need it at all? What am I missing here? No explanations, no guideance, no direction as to what to do or how to do it from Firefox or Mozilla. I can't even tell for sure IF I AM MISSING ANYTHING WITHIN MY WORKING FIREFOX BROWSER NOW THAT WAS SAVED IN THIS BACKUP orrrrrrrrrrr not? lescot lescot@sbcglobal.net

I'm not sure what I did to cause Firefox to do I GUESS a BACKUP. Since I now have a folder named "Old Firefox Data" what do I do with it? Do I need to somehow re-instate all that is in this folder back into my Firefox Browser? Or, do I need it at all? What am I missing here? No explanations, no guideance, no direction as to what to do or how to do it from Firefox or Mozilla. I can't even tell for sure IF I AM MISSING ANYTHING WITHIN MY WORKING FIREFOX BROWSER NOW THAT WAS SAVED IN THIS BACKUP orrrrrrrrrrr not? lescot lescot@sbcglobal.net

Chosen solution

If you have an "Old Firefox Data" folder on your desktop then you must have used the "Reset Firefox" feature, either from the Help -> Troubleshooting Information page , as shown in the screenshot in this article, or from the Firefox Safe Mode window, shown here.

See Refresh Firefox - reset add-ons and settings for more information about this feature.

You don't need the "Old Firefox Data" folder but you can move it to another location on your computer as a backup, if you wish. It's highly unlikely that you have set that folder as your current profile location. To see what folder Firefox is currently using for your profile data, go to Firefox Help -> Troubleshooting Information and click on Show Folder. This will open the Firefox profile folder in Windows. On Windows 7 the default Firefox profile folder would be located here (where "username" is your Windows logon user name and xxxxxxxx is a random string))

C:\Users\"username"\AppData\Roaming\Mozilla\Firefox\Profiles\xxxxxxx.default
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The Firefox profile backup is created if you are resetting Firefox or uninstalling it.
This profile is not needed, but is a good thing to have. This profile can be used to repair any damage to your current profile.


NOTE: If your Firefox application data has only the Old Firefox Profile and no other profiles, DO NOT delete the old profile because Firefox may be running this profile as default.


WARNING: Removing folders/files can cause damage to other programs and the Windows operating system. use caution when manually deleting folders/files. Creating a backup of any deleted files is highly recommended!

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Chosen Solution

If you have an "Old Firefox Data" folder on your desktop then you must have used the "Reset Firefox" feature, either from the Help -> Troubleshooting Information page , as shown in the screenshot in this article, or from the Firefox Safe Mode window, shown here.

See Refresh Firefox - reset add-ons and settings for more information about this feature.

You don't need the "Old Firefox Data" folder but you can move it to another location on your computer as a backup, if you wish. It's highly unlikely that you have set that folder as your current profile location. To see what folder Firefox is currently using for your profile data, go to Firefox Help -> Troubleshooting Information and click on Show Folder. This will open the Firefox profile folder in Windows. On Windows 7 the default Firefox profile folder would be located here (where "username" is your Windows logon user name and xxxxxxxx is a random string))

C:\Users\"username"\AppData\Roaming\Mozilla\Firefox\Profiles\xxxxxxx.default
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Did you have any problems or possibly saw a pop-up that Firefox was starting slow that might have caused you to create a new profile (i.e. reset Firefox)?

When you reset Firefox then a new profile is created and some personal data (bookmarks, history, cookies, passwords, form data) is automatically imported and the current profile folder will be moved to the desktop to an "Old Firefox Data" folder.
Installed extensions and other customizations (toolbars, prefs) that you have made are lost and need to be redone.

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Is there any way to see in the Old Firefox Data folder the extensions and other customizations I had prior to the reset?

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Hi cecer

Your installed extensions can be found in the extensions folder and toolbar customizations are stored in the localstore.rdf file.
Prefs that have been modified are stored in the prefs.js file as user_pref("<pref_name>", <pref_value>);.

What kind of problems did you have that you decided to reset Firefox?

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Thanks so much. I honestly have no idea what happened but Firefox wouldn't stay open and then I got a screen saying I should reset it so I did. Perhaps because I'm on 27.0 beta 2?

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You can check in "Help > About..." which Firefox version you currently have and on which update channel.

If you have submitted crash reports then please post the IDs of one or more recent crash reports that have a "bp-" prefix:

  • bp-xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

You can find the IDs of the submitted crash reports on the about:crashes page.

  • You can open the about:crashes page via the location bar, like you open a website, or open the crash reports page via "Help > Troubleshooting Information".

See:

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ID: bbd7f8cf-1b52-42e3-9622-17d632140118

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cecer, You are replying to a question posted Oct 20, 2013 by someone else. See forum rules and guidelines: ... For support requests, do not re-use existing threads started by others, even if they are seemingly on the same subject.

Please ask a new question and include troubleshooting information for your system, which looks to be Mac OS 10.6.8 based on your crash report bp-bbd7f8cf-1b52-42e3-9622-17d632140118

You can use the link in the Get community support article or this one: