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lost key4.db file

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  • 1 has this problem
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  • Last reply by Stéphane

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My key4.db file went corrupted: no entry in the nssPrivate table! I don't have any backup of that file nor can I use 'Previous version' from Windows. I know the master password. Is there any way to recover my 280 logins/passwords from logins.json without the key4.db file? Thanks in advance for your help, Stéphane.

My key4.db file went corrupted: no entry in the nssPrivate table! I don't have any backup of that file nor can I use 'Previous version' from Windows. I know the master password. Is there any way to recover my 280 logins/passwords from logins.json without the key4.db file? Thanks in advance for your help, Stéphane.

All Replies (2)

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Key4.db is a SQLite database, you can possibly check this file is a SQLite database manager utility.

If you have been using Firefox for a very long time (i.e . have used version 57 or older) and you haven't changed the master password then you may have a key3.db file with a working encryption key. Firefox 71 can still fallback to key3.db if key4.db isn't present. Otherwise I'm afraid that the passwords are lost if you can't find matching logins.json and key4.db files

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Unfortunately no key3.db is present. key4.db is corrupted: no line in nssPrivate table. I have tried to restore the file from system restore point but no luck; the file is corrupted too... I'm afraid I won't be able to solve this problem. Still hoping someone can help.