As long as you did not uninstall Firefox and remove personal data, your old profile still should be in the same location. Depending on how messed up it was, here are two options:

(1) Use the profile manager to start Firefox up in your old profile and create a fresh bookmarks backup. If it didn't run, this won't be useful.

To start in a different profile, Exit out of Firefox and start it up from the Start menu, search box, using

firefox.exe -P

Your old profile may have a name like default.

Then you can create a fresh backup or export of your bookmarks (or both) to a neutral location (e.g., the Documents folder). These articles have the steps for creating these files:

• Restore bookmarks from backup or move them to another computer
• Export Firefox bookmarks to an HTML file to back up or transfer bookmarks (note: does not preserve tags you have assigned to bookmarks, if any)

Exit Firefox, use the profile manager to return to your new profile, then you can either restore the bookmark backup or import the HTML file. The difference is that a restore completely replaces whatever exists now, while an import adds to what you have now.

• Restore bookmarks from backup or move them to another computer
• Import Bookmarks from an HTML file

Success?

(2) Restore an old bookmark backup. Firefox creates these files regularly, but it might not be perfectly complete.

To access the old files, I suggest starting from your current (new) profile folder. You can open that from within Firefox using either:

• "3-bar" menu button > "?" button > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Show Folder" button. This should launch a new window showing your current settings files. Using the address bar of that window, click up to the Profiles folder level and then double-click into your old profile folder, then into its bookmarkbackups folder. Copy the latest backup file to a neutral location (such as your Documents folder).

Back in Firefox, try to restore the older backup. Note: this will completely replace your bookmarks in this profile, so if you have saved new bookmarks you want to save, please perform the optional steps in the following list:

• Optional (preserve new bookmarks): Export Firefox bookmarks to an HTML file to back up or transfer bookmarks
• Restore bookmarks from backup or move them to another computer - use Choose File to go to your Documents folder to get the old backup
• Optional (add new bookmarks to the restored set): Import Bookmarks from an HTML file

Success?

I forgot about recovering your history. Really, there's only one way to do this, which is to transplant the entire places.sqlite database from your old profile to your new one, replacing any bookmarks or history you have accumulated in the new profile. If that's what you want, here's how to do that:

Open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" button > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Show Folder" button. This should launch your current settings files in a new window.

Leaving that window open, switch back to Firefox and Exit, either:

• "3-bar" menu button > "power" button
• (menu bar) File > Exit

Pause while Firefox finishes its cleanup, then rename places.sqlite to something like places.old

In the address bar of that window, click up to the Profiles folder, then double-click into your old profile folder. Find places.sqlite and right-click > Copy it.

In the address bar of that window, click up to the Profiles folder, then double-click into your new profile folder. In a blank area, right-click > Paste to copy places.sqlite here.

Start Firefox back up again. Do you have your old bookmarks and history in the new profile?