Trend Micro recommends requiring strong passwords. Strong passwords usually contain a combination of both uppercase and lowercase letters, numbers, and symbols, and are at least eight characters in length.
When strong passwords are required, a user submits a new password, and the password policy determines whether the password meets your company's established requirements.
Strict password policies sometimes increase costs to an organization when they force users to select passwords too difficult to remember. Users call the help desk when they forget their passwords, or record passwords and increase their vulnerability to threats. When establishing a password policy balance your need for strong security against the need to make the policy easy for users to follow.