Strange Message

["Reasoner, Scott" <SReasoner () BarthElectric com>]

At my organization, we run the Microsoft ISA Server to provide controlled
internet access on our internal network.  This morning when I came in, there
was a Windows Messenger Service message on the screen (like from when you
use the NET SEND command).  It's contents were advertising for college
diplomas (almost exactly the same text as some SPAM I've recieved).  I'm
assuming this means that the ports used for SMB are not being properly
blocked from the internet (something that I know needs to be fixed). 

So, I'm curious, has anyone seen SPAM through the messenger service like
this, or should I be concerned about a system compromise?  My initial
investigation of the machine shows nothing else out of the ordinary.  

The server is running Windows 2000 Server SP3 with all the latest updates
(as of yesterday) installed.  The ISA Server is version 3.0.1200.50 (I found
there is a newer version out which I plan to upgrade to soon).  

Thanks for any help you can provide,
Scott Reasoner
IT Staff
Barth Electric Co., Inc.

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