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dead computer

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  • Last reply by 14brass

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my win7 'puter died and i bought a new one. how do i find bookmarks, passwords etc for both firefox and thunderbird on the old harddisks and implement them into my new win10 'puter?

all i find is how to retrieve them from a running 'puter but not a dead one

thanks in advance

my win7 'puter died and i bought a new one. how do i find bookmarks, passwords etc for both firefox and thunderbird on the old harddisks and implement them into my new win10 'puter? all i find is how to retrieve them from a running 'puter but not a dead one thanks in advance

Modified by 14brass

Chosen solution

Firefox stored your personal data in the profile folder in a hidden location in AppData\Roaming.

  • C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.


You can copy specific files with Firefox closed to the current profile folder to recover personal data.

  • bookmarks and history: places.sqlite
  • favicons: favicons.sqlite
  • bookmark backups: compressed .jsonlz4 JSON backups in the bookmarkbackups folder
  • cookies.sqlite for the Cookies
  • formhistory.sqlite for saved autocomplete Form Data
  • logins.json (passwords) and key4.db (58+) or key3.db (57 and older) (decryption key) for Passwords saved in the Password Manager
    if you only have key3.db then make sure to remove an existing key4.db
  • cert9.db (58+) or cert8.db (57 and older) for (intermediate) certificates stored in the Certificate Manager
    if you only have cert8.db then make sure to remove an existing cert9.db
  • persdict.dat for words you added to the spelling checker dictionary
  • permissions.sqlite for Permissions and possibly content-prefs.sqlite for other website specific data (Site Preferences)
  • sessionstore.jsonlz4 for open tabs and pinned tabs (see also the sessionstore-backups folder)
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All Replies (4)

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If you attach your old disk to your new computer, you can copy the old profile folder from the disk. Where are you stuck in the process?

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where are the files i need?

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Chosen Solution

Firefox stored your personal data in the profile folder in a hidden location in AppData\Roaming.

  • C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.


You can copy specific files with Firefox closed to the current profile folder to recover personal data.

  • bookmarks and history: places.sqlite
  • favicons: favicons.sqlite
  • bookmark backups: compressed .jsonlz4 JSON backups in the bookmarkbackups folder
  • cookies.sqlite for the Cookies
  • formhistory.sqlite for saved autocomplete Form Data
  • logins.json (passwords) and key4.db (58+) or key3.db (57 and older) (decryption key) for Passwords saved in the Password Manager
    if you only have key3.db then make sure to remove an existing key4.db
  • cert9.db (58+) or cert8.db (57 and older) for (intermediate) certificates stored in the Certificate Manager
    if you only have cert8.db then make sure to remove an existing cert9.db
  • persdict.dat for words you added to the spelling checker dictionary
  • permissions.sqlite for Permissions and possibly content-prefs.sqlite for other website specific data (Site Preferences)
  • sessionstore.jsonlz4 for open tabs and pinned tabs (see also the sessionstore-backups folder)

Modified by cor-el