My master password is no longer working.

Hi @555grim

I'm sorry to hear about the trouble with your Master Password. I'd recommend starting with these tips:

If you forgot your Master Password or you can't unlock 1Password

Can I use my backup in Dropbox to repopulate my passwords if I erase and start over?

If you've made a backup then the data in that backup would be encrypted using whatever Master Password you were using at the time the backup was created. If you know what that password is, then restoring from a backup might be a reasonable option. You would lose any data you've entered or changed between when the backup was made and now, though. You can read about backups here:

1Password backups

(scroll to the section on standalone vaults)

If you're syncing your data to Dropbox, then the Master Password used to encrypt the data in Dropbox would be the same as the one you currently need to unlock 1Password. In this case, the data in Dropbox is unlikely to be helpful if you do not have the correct Master Password. You can read more about syncing here:

Sync your 1Password data

I hope that helps. Should you have any other questions or concerns, please feel free to ask.

Ben