The full title of this Knowledge Base article is “You cannot modify the Hosts file or the Lmhosts file in Windows Vista and Windows 7″.
When you try to change the Hosts file or the Lmhosts file in Windows 7, you may receive an error message that resembles either of the following.
Error message 1:
Access to C:\Windows\System32\drivers\etc\hosts was denied
Error message 2:
Cannot create the C:\Windows\System32\drivers\etc\hosts file. Make sure that the path and file name are correct.
This issue occurs even though you log on by using an account that has administrative credentials.
Refer to the for a workaround.