The screen name cannot be an email address or a reserved word

Issue

• When trying to log in with an Active Directory user, sign-in failed with the below error

  ERROR [http-nio-8080-exec-9][BaseSamlStrutsAction:59] Screen name [e-mail] for user 34945 must validate with com.liferay.portal.kernel.security.auth.DefaultScreenNameValidator: The screen name cannot be an email address or a reserved word, such as postfix. It must contain only alphanumeric or the following special characters: -._.

Environment

• Liferay DXP 7.0 to 7.4

Resolution

• The above error will be observed when the screen name is mapped to an email address. Checking the attribute mapping should help.
• Also, since Liferay will allow only the following special characters by default the authentication will not be successful as the email address consists of a special character.

  #
  # Input a list of special characters that are allowed in screen names. This
  # property is read by the default screen name validator implementation.
  # Custom implementations need to also use this property to account for
  # screen names with special characters.
  #
  # Env: LIFERAY_USERS_PERIOD_SCREEN_PERIOD_NAME_PERIOD_SPECIAL_PERIOD_CHARACTERS
  #
  users.screen.name.special.characters=-._

Additional Information

• Connecting to an LDAP Directory