If you want to edit the hosts file in Windows Vista , you might soon realize its not really possible , or it will give you a "file already in use , or cannot be saved" error. So here is the solution.

1)  Browse to Start -> All Programs -> Accessories
2)  Right click "Notepad" and select "Run as administrator"
3)  Click "Continue" on the UAC prompt
4)  Click File -> Open
5)  Browse to "C:\Windows\System32\Drivers\etc"
6)  Change the file filter drop down box from "Text Documents (*.txt)" to "All Files (*.*)"
7)  Select "hosts" and click "Open"
8)  Make the needed changes and close Notepad.  Save when prompted.