SMTP error Dovecot postfix

[aberrio]

Hello,

Using outlook I am getting the following error.

Jan 18 20:22:46 mail postfix/smtpd[19093]: warning: 201.244.200.104: hostname adsl201-244200xxx.dyn.etb.net.co verification failed: Name or service not known
Jan 18 20:22:47 mail postfix/smtpd[19093]: warning: SASL authentication problem: unable to open Berkeley db /etc/sasldb2: No such file or directory
Jan 18 20:22:47 mail postfix/smtpd[19093]: warning: SASL authentication problem: unable to open Berkeley db /etc/sasldb2: No such file or directory
Jan 18 20:22:47 mail postfix/smtpd[19093]: warning: unknown[201.244.200.xxx]: SASL LOGIN authentication failed: authentication failure
King regards,

AL