smtplib bug with Windows XP

[Peter Hansen]

Steve Christensen wrote:
> In article <1106673048.851591.324490 at f14g2000cwb.googlegroups.com>, stewart.midwinter at gmail.com wrote:
>>thank Peter, elbert, for the suggestions.  I hadn't thought of using
>>telnet to try to connect to the SMTP server.  and when I do try, telnet
>>can't connect either, at least on port 25.  On port 110, it has no
>>problem.  So, perhaps the IT people have made some configuration
>>changes; I'll have a chat with them.  I'm relieved that it's not a
>>Python problem, though.
> 
> We had similar issues when our systems were upgraded to McAfee VirusScan
> 8.0. If you're running that locally (on the system trying to connect to
> the SMTP server), try disabling the rule in the Access Control dialog
> that's labeled 'Prevent mass mailing worms from sending email'

How do such tools still allow the sending of valid emails?

-Peter