• Code: 016-506
• Description: Required user entry item is empty Cause: Some item is not set.
• Remedy: The machine will recover after the OK or Close button is pressed or message is displayed for specified time. If the error persists: 1. On CWIS, check if SMTP server or POP3 server is set. 2. Ensure that the error is replicated after the printer is powered Off and then On, and then replace (ESS PWB).

• Code: 016-507
• Description: SMTP Authentication Fail for Maillib Cause: Cannot login to SMTP server to send email.
• Remedy: The machine will recover after the OK or Close button is pressed or message is displayed for specified time. If the error persists: 1. On CWIS, check if user name and password used for SMTP server are set correctly. 2. Ensure that the error is replicated after the printer is powered Off and then On, and then replace (ESS PWB).

• Code: 016-520
• Description: Ipsec Certificate Error Cause: Self device certificate error.
• Remedy: 1. Certificate of self device is invalid. Contact administrator. • Reset the certificate from other connectable client with EWS. 2. If no device can be connected, disconnect cable, turn off IPsec, and then reset certificate with EWS.

• Code: 016-521
• Description: Ipsec Certificate Error Cause: Remote device certification verification error.
• Remedy: 1. Contact administrator. Certificate of destination client is invalid. 2. Confirm certificate of destination client and reset.

• Code: 016-522
• Description: LDAP Certificate Error Cause: No client certificate exists.
• Remedy: 1. Contact administrator. The SSL client certificate is requested by LDAP server. Set the SSL client certificate to the device. 2. Set the LDAP correctly.

• Code: 016-523
• Description: LDAP Certificate Error Cause: Server certificate verification error.
• Remedy: 1. The SSL certificate of LDAP server is not trusted by the device. Register the root certificate of the LDAP server's SSL certificate with the device. 2. Set the LDAP correctly.

• Code: 016-524
• Description: LDAP Certificate Error Cause: No server certificate exists.
• Remedy: 1. Change the SSL certificate of the LDAP server to the valid one. 2. Set the LDAP correctly.

• Code: 016-527
• Description: LDAP Certificate Error Cause: SSL authentication internal error.
• Remedy: 1. Contact administrator. The error has occurred inside the program. 2. Set the LDAP correctly.