Is this the master password or individual passwords saves?

However, if you are talking about sync;

Resetting the sync password, or changing its e-mail, will remove all data from the servers.

This is a security feature. https://support.mozilla.org/en-US/kb/ive-lost-my-firefox-sync-account-information

• I've lost my Firefox Sync account information - What to do
• I’ve forgotten, or don't have access to, my Firefox Account email address

What is the point of resetting then? If I lost all my data that I've been collecting for a long period.

Anyways, I've changed my browser to Chrome. I am sorry guys...I've lost almost everything I got.

We might be able to recover the data, but you need to answer our questions.

please ask

Morrowind said

I've lost all my passwords

What about the rest of your profile? settings, bookmarks . . . . .

They were in my browser Firefox, but it logged out itself

Logged out of what?

I did reset the password, and everything lost

What password was reset? Are you talking about something to do with the Mozilla site?

Mozilla is divided into several separate support/service areas. What are you trying to access?

Look on your desktop. Do you see a folder called; Old Firefox?

https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

I just started Mozilla Firefox browser and found out that it changed. It was like full reset or like new installed. So there were nothing about me, no bookmarks, no passwords. I remembered Mozilla Firefox account login (e-mail) but unfortunately didn't remember password from it. I tryed to reset the password of Mozilla Firefox account (or how you call it, place where all other passwords and bookmarks were), and I did reset it, but it was empty. As password reset deletes all information as I understood later. That's really desappointed me. As I lost all my job and family passwords. Of course I remember some of them, but most of them are now lost.

FredMcD said

Look on your desktop. Do you see a folder called; Old Firefox?

You have not said, but it sounds like you are talking about a sync account.

Resetting the sync password, or changing its e-mail, will remove all data from the servers.

This is a security feature. https://support.mozilla.org/en-US/kb/ive-lost-my-firefox-sync-account-information

• I've lost my Firefox Sync account information - What to do
• I’ve forgotten, or don't have access to, my Firefox Account email address

However, while the data on the sync servers is removed, the data in the Firefox profiles using the sync is not changed.

Using any of the other devices on the sync, create a new sync account. Then install the other devices on the new sync.

The password of the Sync account is used to encrypt your personal data locally before uploading to the Sync server.because you forgot it then the new password won't be able to decrypt data that had been encrypted with another password. So thr password is used in two ways, to authenticate on the Sync server and to encrypt your personal data locally. Data that isn't encrypted never leaves your computer.

Note that Sync isn't meant to be used as a backup device and you should always backup your personal data.

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

so, it means all my data lost irretrievably?

Morrowind said

so, it means all my data lost irretrievably?

Yes.

Sync data can't be decrypted after a new / different Password is created for the account; the old Password was used to create multiple keys which are used to encrypt user data so that no one except the the user can ever view or use that data. So your data was deleted from the Sync server when you did the Refresh; your data sitting on the Sync server was rendered useless when doing the Refresh.

I guess you missed the warning message when doing the Refresh. see the screenshot

Don't you have any backup of files in the profile folder?

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

You can look at this utility to browse System Restore points.

• System Restore Explorer http://nicbedford.co.uk/software/systemrestoreexplorer/

In the event that the passwords information is lost, you should record all information in a separate text file somewhere else on your hard drive, or written down. You can easily copy and paste if you need to do so. If you are concerned about someone else looking at that file, you can compress it using a password.