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HD failure. Want to use former Firefox profile which is undamaged. How to use it rather than the one created by reinstallation of Firefox on rebuilt box?

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  • Last reply by scoxbike

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I've had a hard drive failure. The former Firefox install's profile (directory tree and directory's data) is undamaged. How can I get Firefox to use this old profile rather than the nice new one that it so pleasantly created when I re-installed Firefox on rebuilt Windows box? Profile Manager gives options to Create, Rename or Delete a profile. I don't want to do any of these three options. I simply want to use an existing profile in place of the one that the re-installation created. How to get Firefox to use an alternate profile? Command line option for Firefox itself? Profile Manager option to make a chosen profile the default one? As a fine detail, where should I place the root of the old profile's directory tree for its use once all of this is completed? I can't tell from what I've read so far whether one profile alone lives under "c:\Users\yadda\AppData\Local\Mozilla\Firefox\Profiles\" or all of them do, assuming one has several profiles. I've copied my former profile tree to under this spot but can't find any directions about how to just load my desired profile in place of the default one. Assistance greatly appreciated, thanks.

I've had a hard drive failure. The former Firefox install's profile (directory tree and directory's data) is undamaged. How can I get Firefox to use this old profile rather than the nice new one that it so pleasantly created when I re-installed Firefox on rebuilt Windows box? Profile Manager gives options to Create, Rename or Delete a profile. I don't want to do any of these three options. I simply want to use an existing profile in place of the one that the re-installation created. How to get Firefox to use an alternate profile? Command line option for Firefox itself? Profile Manager option to make a chosen profile the default one? As a fine detail, where should I place the root of the old profile's directory tree for its use once all of this is completed? I can't tell from what I've read so far whether one profile alone lives under "c:\Users\yadda\AppData\Local\Mozilla\Firefox\Profiles\" or all of them do, assuming one has several profiles. I've copied my former profile tree to under this spot but can't find any directions about how to just load my desired profile in place of the default one. Assistance greatly appreciated, thanks.

Modified by scoxbike

Chosen solution

The important folder is under AppData\Roaming, not AppData\Local. Local just has temp stuff like cache, and you can ignore that.

If you want to do a wholesale restoration, you could try the old profile resurrection method in the following thread. Where it refers to Old Firefox Data, you'll instead look at your data from your old hard drive.

https://support.mozilla.org/questions/1090699

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First; open your file browser to the New profile;

Type about:support in the address bar and press enter.

Under the page logo on the left side, you will see Application Basics. Under this find Profile Folder. To its right press the button Show Folder. This will open your file browser to the current Firefox profile. Now Close Firefox.


Second, open the file browser to the Old profile.

Open another file browser to the Old Firefox folder.

Warning ! ! Only Copy the files you are told. We will avoid anything that might be the cause of your problems. Here is the list of files;

cookies: cookies.sqlite Do not bother. Cookies will be created when you return to the website. However, you will have to log in everywhere. And you may lose any settings that websites store on your computer.

extensions(add-ons, themes): it would be better to download them fresh. +++++++++++++++++++++++++++++++++++++++++++++++++ key3.db and logins.json : These are the Password files. Copy Both !

persdict.dat : custom dictionary – words you added to the dictionary

mimeTypes.rdf : What to do with what type of file.

places.sqlite : History and Bookmarks.

prefs.js : Your settings. Note, If you were having problems, this could be contaminated.

cert8.db and possibly cert_override.txt : Stores all your security certificate settings and any SSL certificates you have imported into Firefox. If removed, the file will be replaced.

search.json.mozlz4 file stores the user-installed search engines that are available in the Firefox v45+

search.sqlite file and searchplugins folder store the search engines that are available in the Firefox Search bar. +++++++++++++++++++++++++++++++++++++++++++++++++ Copy these files from the old to the new. You will get a message that the files already exist. Choose to over-write for each file.

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Chosen Solution

The important folder is under AppData\Roaming, not AppData\Local. Local just has temp stuff like cache, and you can ignore that.

If you want to do a wholesale restoration, you could try the old profile resurrection method in the following thread. Where it refers to Old Firefox Data, you'll instead look at your data from your old hard drive.

https://support.mozilla.org/questions/1090699

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Thanks to both jscher2000 and FredMcD. I didn't realize that the important stuff was under AppData\Roaming until I started twiddling with FredMcD's instructions. Then the light glowed brighter. Along with "places.sqlite" I also had "places.sqlite-shm" and "places.sqlite-wal". Only once I copied them too, did my bookmarks and bookmarks toolbar reappear. All in all, everything looks like its all back to the pre-crash state. Beers to both of you for your help. Now on the the zillion other application re-installs....