traceing instant message

You would basically need to be logging all DNS activity.  On Linux machines, named can do this.  On Windows machines you will most likely have to resort to Network Monitor packet capture or download and use Ethereal for a packet capture.  A third choice would be logviewer:

Ethereal:      http://www.Ethereal.com/
LogViewer:  ?

I can't believe how many people have infringed Sven Schaefer's copyright!  It's really not nice when you take the name of someone else's work and live parasitically from him.

Sven Schaefer has the best Windows packet capture there is; apparently, a lot of plagiaristic companies and people know it and want to steal that name from him, LogViewer.  As far as I'm concerned, he was the first and he owns the rights to the name.

He should sue the others.

But Ethereal or Network Monitor will work, you'll just have to do more reading and they're a bit more to install.

And now I have to get ahold of Sven and ask if he'd like some help in ending this parasitic group of software coders and companies.

No, you won't be able to. As I understand it, YIM uses a centralised service so users are anonymous in that sense.

If you want to get rid of unwanted messages, click on the messenger tab and select the privacy options to ignore someone.

Hi,

I think ethereal give you only ip of the yahoo server not third person. You can also try with the Netstat
go to run > netstat

Its show the yahoo server ip not third person.

If you send a file to the other party through Yahoo and then type NETSTAT -A in a DOS-window you see the IP address of that person...