suspicious firewall rules in WinXP firewall

[belka () att net]

While setting a port for Symantec to query XP Pro workstations for virus updates, I noticed two machines that had 
firewall rules (exceptions in WinXP firewall parlance) that were in unreadable charcaters, such as an asian font set 
that couldn't be displayed. The rule name was in blocks or in other unreadable characters.  The user of these two 
workstations is notorious for downloading asian TV shows over bit torrent, and visiting anime and other asian sites.

I deleted the two firewall rules (DOH! I should have just disabled them) and now IE and Mozilla browsers do not work at 
all.  I can ping out of these two machines, and as long as I use an IP address, these machines can ping anywhere in the 
Internet.  However, if any call to DNS is requires, either with a browser or ICMP, it fails.

Has anyone had a similar experience or seen this kind of behavior.  My fear is that one of the "special Korean download 
programs" that this user admits installing has altered the browser or -- even worse - the XP TCP/IP stack with hooks 
into a trojan or spyware product.  I tried disabling the firewall to allow all traffic in and out, but to no effect.  
No DNS functionality.  My packet traces are inconclusive and my IDS is not alerting on anything in or out of these two 
work stations.

Any ideas?  At this point I know I am going to have to reload, but from a forensic stand point, I am curious if any one 
else has seen this kind of beavior before.

Thanks.

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