Windows defender warning after scan

[Scouse]

After scanning with windows defender it says i have a settings modifier in
windows\System32\drivers\etc\hosts.
It says it is Win32/PossibleHostsFileHijack.
I quarantine the item but it comes back at next reboot.When I clean item it
fails as it says it might be aread only.
How do i remove this from pc as when I search for it i cant find it
I am running windows vista.

 

[Engel]

http://www.answers.com/Win32/PossibleHostsFileHijack

 

[C.B.]

After scanning with windows defender it says i have a settings modifier in
windows\System32\drivers\etc\hosts.
It says it is Win32/PossibleHostsFileHijack.
I quarantine the item but it comes back at next reboot.When I clean item
it
fails as it says it might be aread only.
How do i remove this from pc as when I search for it i cant find it
I am running windows vista.

Scouse,

Did you click on a link in an instant message or email? This sounds
like malware to me. You may be able to remove it from your system, but then
again, maybe not. Run a Hijack This scan and send the results in for
analysis.

If all methods of removal fail your only recourse is to reformat and
reinstall your OS. You should backup all your important files and data
before reformatting and reinstalling.

Have a nice day.

C.B.