|Excel Developer Reference|
expression.Protect(Password, Structure, Windows)
expression A variable that represents a Workbook object.
|Password||Optional||Variant||A string that specifies a case-sensitive password for the worksheet or workbook. If this argument is omitted, you can unprotect the worksheet or workbook without using a password. Otherwise, you must specify the password to unprotect the worksheet or workbook. If you forget the password, you cannot unprotect the worksheet or workbook.|
Use strong passwords that combine uppercase and lowercase letters, numbers, and symbols. Weak passwords don't mix these elements. Strong password: Y6dh!et5. Weak password: House27. Passwords should be 8 or more characters in length. A pass phrase that uses 14 or more characters is better. For more information, see Help protect your personal information with strong passwords.
It is critical that you remember your password. If you forget your password, Microsoft cannot retrieve it. Store the passwords that you write down in a secure place away from the information that they help protect.
|Structure||Optional||Variant||True to protect the structure of the workbook (the relative position of the sheets). The default value is False.|
|Windows||Optional||Variant||True to protect the workbook windows. If this argument is omitted, the windows aren’t protected.|