From MozillaZine Knowledge Base

Starting in Firefox 3, you can replace your current bookmarks with a backup file using the "Restore" feature of the Bookmarks Manager ("Bookmarks -> Organize Bookmarks -> Import and Backup -> Restore").

Exit Firefox completely (or reboot the computer) and reopen Firefox. If the "Restore" feature now works, a previous Firefox process may not have closed properly. If this is a recurring problem, see this article. [1] [2] [3]

If you still see the problem, even when you first open Firefox after restarting the computer, the JSON bookmark backup file you are trying to restore may be damaged. Bug fixes in Firefox 3.0.5 have reduced the likeliness of this occurring so make sure you update Firefox if you are using an older version of Firefox 3. [4] [5] If you are still seeing this problem in Firefox 3.0.5 or later, even in your most recent bookmark backup files, try the following:

• There are reports that PC Tools Spyware Doctor may cause this and other Firefox bookmarks issues, such as inability to delete, move, or edit bookmarks. Stop using the software and follow the below instructions for a damaged places.sqlite file to clear up any remaining bookmarks issues. [6] [7] [8]

• Check the permissions of the bookmark backup file you are trying to restore (e.g., "bookmarks-2008-11-01.json") to make sure you have access to the file, especially if you copied the file from another computer. [9]

• Create a new Firefox profile and see if you are able to restore the bookmark backup file in the new profile. [10] You can use the "Import and Backup -> Restore -> Choose File..." feature of the Bookmarks Manager to restore the backup file of your choice, including one of the "bookmarks-(date).json" backups from the bookmarkbackups folder of the original Firefox profile folder. If that works, you can export the bookmarks again to an HTML file and then import that bookmarks HTML file in the original profile, or you can keep using the new profile. Note: If you are unable to restore a JSON backup that was created in your original profile, the JSON backup file and possibly the places.sqlite file in the old profile may be damaged. [11] You can try fixing your old profile by replacing or rebuilding the places.sqlite file (see below) or go thorough the other standard diagnostic steps to troubleshoot extensions or other problems in your original profile.

Damaged places.sqlite

Your Firefox bookmarks and browsing history are stored in the Places database file, "places.sqlite". If there is a problem with this file, it can affect a number of functions related to bookmarks and history, including the "Import and Backup" features of the Bookmarks Manager. If you have a recent profile backup you can try replacing the original "places.sqlite" with the backup copy.

If you have no backup or if it doesn't resolve the issue, you can force Firefox to create a new copy of places.sqlite and rebuild the Places database as follows: (You may wish to export your bookmarks to an HTML file first, as a precaution.)

1. Close Firefox completely
2. Open the Firefox profile folder
3. Remove or rename all files named "places.sqlite", including "places.sqlite.corrupt" files and "places.sqlite-journal", if found.

Note: In case there is a problem with the JSON bookmark backups, you may also wish to remove all "bookmarks-(date).json" files from the bookmarkbackups folder and optionally place a recent copy or export of bookmarks.html in the Firefox profile folder. (This will result in missing bookmarks if the Firefox profile folder does not contain a "bookmarks.html" file with current bookmarks.)

When you next start Firefox, "places.sqlite" will be rebuilt; however, you will lose your browsing history of recently visited pages. Your bookmarks will be automatically restored from the latest JSON bookmark backup or, if no JSON backup file is found, Firefox will automatically import the bookmarks from the profile folder bookmarks.html file, if it exists. [12] [13]

See also

• Locked or damaged places.sqlite

Related bug reports

• Bug 448584 - Don't save invalid uri nodes while doing a JSON backup (don't stop while saving data) (fixed in Firefox 3.0.5)
• Bug 458683 - Backup only uri nodes into tag containers (fixed in Firefox 3.0.5)