Postfix SMTP server: errors from unknown[xx.xx.xx.xxx]

[levaska]

I am getting 5-6 error to my admin email..

Pls Help me about this..

Transcript of session follows.

Out: 220 vps-100000-0000.servercompany.pl ESMTP Postfix (Debian/GNU)
In: EHLO lteknik
Out: 250-vps-100000-0000.servercompany.pl
Out: 250-PIPELINING
Out: 250-SIZE 10240000
Out: 250-ETRN
Out: 250-STARTTLS
Out: 250-AUTH CRAM-MD5 LOGIN PLAIN DIGEST-MD5
Out: 250-ENHANCEDSTATUSCODES
Out: 250-8BITMIME
Out: 250 DSN
In: STARTTLS
Out: 454 4.7.0 TLS not available due to local problem

Session aborted, reason: lost connection

For other details, see the local mail logfile