Windows Vista Security Center

Hi

I am having problems with the security center.

1. I have had Windows Defender installed on my PC from the beginning, I
never deactivated it and it has run smoothly. It has downloaded new
definitions and seached the PC as it should.
Problem: The security center tells me that Windows Defender is NOT active
(even though it is). I have checked the Help and went to the Defender Setup
screen and all is as the Help suggests.

2. I didn't have an antivirussoftware installed in the beginning. I have
recently installed AVG's software (free version). Windows Vista Help tells me
that this is supported by Vista.
Problem: The Security Center tells me that it couldn't find any
antivirussoftware and suggests AVG. But I already have the software and made
sure that it is the latest version (v. 7.5.476 09. Aug. 2007). It has also
made the first scan and has been set up to do daily scans, all at recommended
levels.

Any help to why my Security Center is malfunctioning will be welcome

ThX

--
Best regards
Nuitarius