Expert: James Filmer - 11/23/2008

Question
My computer recently has some program that sends out 'packets' and receives 'packets' all the time via my wired high speed modem.  The effect is to slow the modem to 10 of its speed.  At one point everything cleared up and the speed came back (5 Mbytes - with a ping of 60 millisec) so I thought the problem was cured - but I rebooted again today and the Internet activity started again and the speed dropped to 500kb and the ping was 800msec (vis speedtest.com) - how do I find the program that is sending out and receiving all the packets - I assume something is working - how do I stop it?  I have Trend up to date and Spybot up to date.  I should sayt that when I disable the netword card - then the speed for other computers on the Internet-modem goes back up to normal.  So it is something on this single computer that started suddenly about a month ago.  Because there was a time last week when everything was ok and now it is slow immediately after a reboot I have to assume that there is a program launching that is doing this - but how to locate?  How can one identify programs sending network traffic?  Thank you.

Answer
Without knowing the system your using, more about your network (card, firewall...), at least some of your other applications besides Trend and Spybot, and which version of Trend Micro you're using, it's almost impossible to determine what the real problem is.
For example, Trend Micro AntiVirus plus AntiSpyware causes significant computer slowdowns occasionally.

One of more of the following tools may help you identify programs sending network traffic. ((Some Firewall programs also have this feature).

http://www.netmon.org/tools.htm

Also, Trend Micro conflicts with some applications (especially certain Firewalls). But again, impossible to determine without more info about your the version you're using.

If you're on Windows, Windows Task Manager can be used to monitor your system's CPU usage - The highest CPU-using process is at the top of the window.

http://www.merijn.org/programs.php also has HijackThis and Startup List with autostart locations, and a list of launch points.

If you save the HijackThis report, myself or someone else here can likely help you interpret the scan results, and Startup List 2.02 a great free tool for all Windows systems (if you're on Windows)

Finally, you might consider (via search engine) seeking info about Trend Micro issues such as: http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleI... which could degrade your PC's performance.