Your authentication setting for the Store Print Log to Network feature is not correct.

Check the following points.

• Make sure the Username and Password in Authentication Setting are correct. If the username is part of a domain, enter the username in one of the following styles: user@domain or domain\user.
• Make sure the time of the log file server matches the time from the SNTP server, or the Date&Time settings.
• Make sure the SNTP time server settings are configured correctly so the time matches the time used for authentication by Kerberos or NTLMv2. If there is no SNTP server, make sure the Date&Time and Time Zone settings are set correctly using Web Based Management or the control panel so the machine matches the time being used by the server providing the authentication.