iphone restore from backup

You put a password on your backup, whether you remember doing so or not. That’s the only way encrypted backups get created. Either you checked Encrypt Backup, or, if you have a company email account on your phone, your Exchange administrator required it. But either way you were prompted to enter a password - twice. However, that could have been years ago; you are only prompted the first time you made an encrypted backup, you will never be prompted again until you go to restore a backup.

When you entered the backup password if you have a Mac and have Keychain enabled you were given the option of saving the password in Keychain (this is the default). So check Keychain for it.

If you haven’t erased the phone yet you can create a new backup with a new password—>About encrypted backups on your iPhone, iPad, or iPod touch - Apple Support

If neither of those work you get unlimited guesses, so try to guess what password you might have entered back when. If you are like most people it will be a password that you reused. And to speed up the process click to change the password and you will be prompted immediately.

Note that if you do NOT encrypt your computer backup then the backup will be incomplete; it will not include health data or passwords. iCloud backups are protected by default because they require your Apple ID and password to access, so this is not an issue for iCloud backups.

It appears that you have forgotten the password to the encrypted backup that was created from your old iPhone. You will need that password or you will not be able to use that backup. Do you still have your old iPhone with the data still on it? If YES, then you can create another backup and then restore your new iPhone from it. I have a feeling that you no longer have your old iPhone. If this is the case and you do not have the right password to the encrypted backup, then you can try and restore your iPhone from an iCloud backup file. This is if you used iCloud with your old iPhone. Did you use iCloud for Photos, Messages etc?

Axel F.

You need to have the the encryption password you used during backup otherwise anyone could find your backup file and restore it to their phone,

Without it your data is inaccessible.