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Why Firefox Failed to Process a Backup File?

written by: Donna Buenaventura•edited by: Bill Fulks•updated: 9/30/2010

You are trying to restore the Firefox bookmark backup file, but Firefox is unable to process the backup file. There are plenty of reasons why Firefox may fail to restore your bookmarks and here's why (with possible solutions).

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    Bookmarks and Firefox Backup Feature

    Firefox Unable to Process Backup File Mozilla added a feature in Firefox 3 that does allows you to backup and restore your bookmarks. Old versions of Firefox only allow importing and exporting of bookmarks in HTML file format. Starting with Version 3 of Firefox, you can now backup your bookmarks without the need of a third-party extension. However, in some cases Firefox is unable to process the backup file. There are several reasons why Firefox failed to restore bookmarks. Check the sections below to try fixing the issue before you re-install the Firefox browser or re-create the bookmark.

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    Firefox.exe Still Running or Version of Firefox is Old

    A known issue with using the restore function of Firefox 3 when restoring the backed-up bookmarks has been fixed in the newer version of Firefox. If you are still using the old version of the browser, upgrade to the latest release to take advantage of the bug fixes. If you prefer using an old version, don't use the said feature in Firefox to restore or backup bookmarks. Use a third-party backup and restore manager instead e.g. Firefox Environment Backup Extension (FEBE).

    If you are using the latest but not the greatest version of the Firefox browser and you are seeing the error "Unable to process a backup file", ensure that Firefox has completely shutdown before trying to restore a bookmark backup file. Verify by checking the running processes in Windows via task manager.

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    Anti-Spyware Program, Permission Issue or Corrupted Profile

    If you are using anti-virus or anti-spyware programs that monitors or guard the settings, files or processes of Firefox, temporarily disable the protection for Firefox or browsers. PC Tools Spyware Doctor with Antivirus has been reported to interfere or block the process of restoring Firefox backups for bookmarks.

    However, if you are not using any security program that guards Firefox settings or files, you are maybe backing up a json file (Note that the backup of bookmarks have a file extension .json) that is not permitted to be copied. This is true if you copied the backup file from another PC or user profile that has different permissions from what you have.

    Make sure that the current Firefox profile isn't corrupted. Try creating a new profile in Firefox and restore the backup by browsing to the bookmarksbackup folder:

    • For XP: C:\Documents and Settings\<user name here>\Application Data\Mozilla\Firefox\Profiles\<xxxxxxxx.default>\bookmarkbackups
    • For Vista and Windows 7: C:\Users\<user name here>\AppData\Roaming\Mozilla\Firefox\Profiles\<xxxxxxxx.default>\bookmarkbackups
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    Locked or Damaged "Places.sqlite" File

    The image at the right is where you can manage the bookmarks. To open the bookmark backup feature in Firefox 3Firefox Bookmark manager  and higher, click on the "Bookmarks" menu and then select "Organize Bookmarks".

    If you try to restore a backup file and see an error message stating "Unable to process a backup file", the "places.sqlite" in Firefox profile folder is maybe locked or damaged, especially if you tried to edit or modify the said file using SQLite manager add-on for Firefox. To fix the problem, try the following steps:

    Warning: You should only use this step if there's no anti-virus or anti-spyware program that guards or monitors the files or settings of Firefox. Temporarily disable your antivirus or antispyware software before proceeding.

    • Close Firefox browser and ensure that there is no firefox.exe running in the background. Verify this by opening the Task Manager in Windows, and then end the processes of firefox.exe, if listed.
    • Open the Profile folder in Firefox e.g. 0mvl5xuy.default folder which is located in the following directory, depending on your operating system: C:\Documents and Settings\<user name here>Application Data\Mozilla\Firefox\Profiles in XP; or C:\Users\<user name here>\AppData\Roaming\Mozilla\Firefox\Profiles in Vista and Windows 7
    • Rename or remove all files named "places.sqlite", including "places.sqlite.corrupt" files and "places.sqlite-journal", if exist.
    • Open Firefox to allow the browse in rebuilding "places.sqlite" file and restore bookmark file from the bookmarks.html file, which is in the same folder where "places.sqlite" is stored.

    Image credits: Firefox logo from, screenshot taken by the author.

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