If you want my straight recommendation, I'd leave the hosts file at the
installed default, which contains exactly one active line--
127.0.0.1 localhost
Microsoft Antispyware will show this as an empty hosts file, so I'm not sure
what the choices are that you are seeing. According to the help, you can
choose to "deactivate" or "remove."
Deactivate should be reversable--I'm not sure how this is done, but the
logical way would be to turn the lines into comments--this is easily done.
If you want to work with the hosts file, the Microsoft Antispyware system
explorer hosts file explorer is a miserable way to do it. You'd be much
happier with a tool made for the purpose, such as:
http://www.funkytoad.com/hoster.htm
This has a one button solution to take you back to the original hosts file.
If you want to fill it up again with sites that it will prevent you from
accessing, I believe it is Spybot Search and Destroy that provides that
list, or, you can use the Microsoft MVP's hosts file, found here:
http://www.mvps.org/winhelp2002/hosts.htm
and updated just 3 days ago.
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