If you try to update a file that Windows7 considers to be “protected”, like the hosts file, you will get an “Access Denied” error when you try to save it. The way around this is to run the program required to update the file as administrator. For example, you might use notepad to update the hosts file. To run notepad as administrator, click the “Start” button and enter notepad in the search field. Right click on notepad and select “Run as administrator”. Then just make your changes and save the file as you normally would.