I’ve decided to dump AVG in favor of Microsoft Security Essentials. Upon
installation, I received the following message, “Windows Firewall is still
turned off for some unknown error. Try turning it on manually from Windows
Security Center.” So I went over to the Control Panel and fired up the Windows
Firewall. It said that it was already on. Now, I’m not overly concerned because
this is my desktop computer sitting behind a NAT router. So if I understand
correctly, the Windows Firewall is not really necessary. However, I have some
concern that maybe something with the firewall is wrong and not properly
functioning even though it says it’s on. The initial quick scan of MSE found
the Broadcast DSS agent software with one of our old kids’ games.
In this excerpt from
Answercast #65, I look at a system that is displaying odd behaviors in the
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So I am little concerned myself.
One of the things that malware often does is disable or otherwise corrupt
the firewall that might be installed on your system in order to allow other
malware to get on board. I’m not saying that that’s what has happened in this
case, but the fact that you did find some malware on that machine (that
apparently AVG did not) leads me to believe that it’s at least something to be
Technically, you’re absolutely right; I would be perfectly comfortable with
leaving the Windows firewall off if you’re behind a NAT router.
A NAT router prevents basically all unrequested outside contact from the
internet. The only way to get a connection to something on the internet is if
your machine initiates that contact out. Any contact coming
in from the internet that wasn’t a part of the conversation your
computer initiated can’t reach your computer.
That’s why a NAT router is such a good firewall.
So with all that as kind of backup, I guess what I would suggest you do is
see if you can’t run a repair reinstall of Windows. I don’t think you included
which version of Windows you’re running.
I’ve got a couple of different of articles on that, that you might check
In Windows XP, there actually is an explicit “repair” option on the install
In Windows 7, you basically perform what’s called an “update install” of
Windows 7 on top of your existing installation.
Naturally, as you might expect, given that you’re going to be doing
something fairly major in terms of a repair install; I would suggest that you,
of course, backup that machine completely before you start.
I don’t think there’s really anything horribly concerning here; but I agree
with you that this is somewhat unsettling. I’d probably see if I couldn’t get
this issue resolved with a repair reinstall.
Next from Answercast #65 – Why
do some smartphone photos come out upside down?