Q: Missing Bookmarks after Upgrading to Firefox 3
A: If you upgraded from Firefox 2 to Firefox 3, some of your settings and bookmarks could have lost. To retrieve them, follow these steps:
1. Close Firefox
2. Open your profile folder. The location of a default profile folder is determined by the operating system you’re using:
For Windows Vista/XP/2000 - %APPDATA%\Mozilla\Firefox\Profiles\your_default_profile_folder\
For Windows 98/Me - C:\WINDOWS\Application Data\Mozilla\Firefox\Profiles\ your_default_profile_folder \
3. In the bookmarks and history files, rename places.sqlite to places.sqlite.bak, and the .json files in the bookmarkbackups folder to .json.bak.
Note: If the .txt file extension is not shown, rename signons3 to signons3bak
4. Start Firefox.