In Vista, normal users are not allowed to save the hosts file, so the easiest way to edit it is to run notepad as an administrator.
- Go to start and either search for “notepad” or go to All Programs > Accessories
- Right click “notepad” and select the “Run as Administrator Option.”
- Once Notepad opens go to File > Open and browse to “C:\Windows\System32\Drivers\etc”
- Set the file filter to “All Files”
- Select and Open “hosts”
- Edit it and save it.
If you get an error about it being read only:
- Go to File > Open, right click the “hosts” file and select properties
- Uncheck read-only at the bottom and click OK.
- Click Cancel to go back to notepad”
- Save it