Defender Vista 64 - permenantlty turned OFF

[Guest]

Windows Defender Version: 1.1.1505.0
Engine Version: 1.1.2803.0
Definition Version: 1.21.2840.5
Vista 64 - Build 6000 all updates
Intel Core Duo / ASUS P5B / DDR2 800 / ATI

From a few months ago, the red X has appeared in the bottom right corner,
and the selection for on/off is set to off. When i try to turn this on it
says it can't locate any new definitions. As this is built into the OS, how
do i get around it and "re-install".

I though it was OK, as it was doing scans and udating according to the
security logs, BUT having just Downloaded a trail anti-malware program from
Avast, i noticed i had a worm on the system, that was undetected as well as a
number of undesirable files

 

[Dave M]

Mark;

Though I don't have Vista and am not sure what you mean by a red X, it
appears your Defender is up-to-date as far as Defender Version Engine
Version and Definition Version, as you can see by looking at Engle's post
immediately below your own. Can you give us more detail about the red X
does it say anything else? Are you getting pop-up messages? Also what
selection for On-Off, are you talking about, the Security Center
notifications? (that's not a component of Defender)

What did you have for Anti-Virus protection before you downloaded Avast?
Windows Defender is not an Anti-Virus, and the detection of Worms and
Trojans is usually the province of A-V security software, but there can be
overlap. What did you do about the Avast detections, remove or quarantine
them?

 

[Bill Sanderson MVP]

Are you sure the system is clean? I know that the current Storm worm
disabled another Microsoft antimalware program as well as the Windows
firewall on a system I work with. This is to be expected--it's a
trojan--the user was local admin, and assented to running the trojan, which
was then able to do whatever it pleased.