Ref: http://www.winvistatips.com/security-log-eventid-529-smtp-t673781.html Ref: http://www.pcreview.co.uk/forums/thread-1596278.php Bad guys are trying to authenticate server via port 25. How to reproduce this log: # Type telnet 25,and then press ENTER. # Type EHLO , and then press ENTER. # Type AUTH LOGIN. The server responds with an encrypted prompt for your user name. # Enter your user name encrypted [...]