I am running a Windows XP SP2 and have a broadband internet connection. Every
now & then I get the annoying message 'There is an IP address conflict with
another system on the network' in the system tray. This doesn't hamper the
performance of the system or browsing in any way but I am tired of getting
the message. Can anyone help me please.

You may want to use ARP –a command to find the Mac address of other device. This search result may help,

System has detected IP conflict The system detected an address conflict for IP address 192.168.1.100 with the system having network hardware address 00:0C:41:9B:88:89. Cause: There is ...
      www.chicagotech.net/troubleshooting/eventid4199.htm 


Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
  I am running a Windows XP SP2 and have a broadband internet connection. Every
  now & then I get the annoying message 'There is an IP address conflict with
  another system on the network' in the system tray. This doesn't hamper the
  performance of the system or browsing in any way but I am tired of getting
  the message. Can anyone help me please.

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