There are two types of wallets in MultiBit Classic. They are:
Password protected wallets are much more secure than non password protected ones. It is recommended that you password protect all MultiBit Classic wallets.
You can add a password to a wallet using the 'File | Add Password' menu option.
MultiBit recommends using a password manager like LastPass or KeePass to generate a one-off password with at least 14 random characters.
Do not lose the password that you use for a wallet!
You need your password to spend your bitcoin. There is no way to recover your password if you lose it.
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