DNS resolution Issue nslookup works, but web/ping doesn't [duplicate]
Check your hosts file, although I don't think that's likely to be the cause.
Disable the XP firewall and test.
Try net stop dnscache then net start dnscache. This seems to do something that ipconfig /flushdns doesn't, IMX.
Delete the arp cache: netsh interface ip delete arpcache
Check your routing table: route print
Try flushing your DNS cache on the machine by running this from the command line:
ipconfig /flushdns