do anyone know what this is - my internet hasnt connected most of the day and when I eventually got a connection a message came up in a yellow triangle saying "connection conflict with another system on network" is this a problem? its now gone by the way
Sounds like the WEP key has been cracked. You'll have to log in to the router and change the security key and also change it to WPA. Your router software should give you a choice. You'll need to re-set the connections for your wi-fi PCs with the new security type and key.
I log in to my D-Link router by typing 192.168.1.1 in internet explorer's address bar. You'll need the user name and password. If you've not done this before then search for the default log in name and password for your particular router. You should always change these when you use as a router matter of routine.