blue probably ur dns resolver is not working.. or the zone file/hosts files under windows is corrupted.. to fix this go to the run menu
ctrl + r
then type cmd (command)
it will bring the command prompt.. type this
ipconfig /flushdns
you'll then have a brand new zone file for the resolver to resolve... but it will occur again.. thats a problem with windows xp... it saves both succesful resolves .. and unsuccessful ones.. u can fix it from the registry or u can use third party softwares like
treewalk dns .. its is a dns cache/ resolver program.. which bypasses the windows's built-in resolver.. and its easy to update/flush and reload..
to update the registry for not saving the unsuccessful dns requests.. u can do this.. add a DWORD value in....
go to run menu (from the start menu or press ctrl+r.. then type regedit)
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet
\Services\Dnscache\Parameters
DWORD: MaxNegativeCacheTtl
Value: 0
and also u can change the TTL value.. to 4 hrs.. from 24hrs.. default in windows xp.. the benefit of that is.. u will always be updated within 4 hrs..
add a DWORD to the registry..
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Dnscache\Parameters
DWORD: MaxCacheTtl
Value: 14400
NB - make sure you enter the 14400 (seconds) as Decimal Base and NOT Hexadecimal Base!
CAUTION : DO NOT TRY IT UNLESS YOU KNOW WHT YOU'RE DOING.. i learnt it from somewhere else.. and worked for me.. so try it at your own risk