Account usernames, passwords, and private encryption keys must be:
• 4 to 50 ASCII (English) characters in length
• no ASCII control characters
• no "@" symbol (other than the standard 1 in an email address, for the username)
Backblaze allows you to specify an optional private encryption key for additional security of your backups. If you select this option, you will absolutely need this key to restore your data. If you lose this key, you will lose the backed up data, and Backblaze employees can not retrieve that key for you - so please keep it in a safe place.