Select Start -> Settings -> Control Panel:
Double-click the 'Network and Dial-up Connections'
folder:
Select your ethernet or wireless adapter (single click):
Right click on your ethernet or wireless adapter's icon and select
'Properties':
Select 'Internet Protocol (TCP/IP)' and click
'Properties':
Check that 'Obtain IP address automatically' and
'Obtain DNS server address automatically' are selected, and
click 'OK':
