Security Alert: Malware protection is OFF

[matsonusa]

My wife's laptop pops up a "Windows Security Center" alert in her tray periodically (few times a day) and firing up the Security Center says her "Malware protection" has been disabled.  If we wait long enough, it re-enables itself (5 - 15 mins?)

Irritation factor: High
Threat factor: Unknown

Her LT: Sony VAIO, Vista Sp1, 2 months old.

My LT: HP Entertainment, Vista Sp1, 6 months old.

Both laptops:
Firewall: Comodo (mine), Windows Live OneCare (hers)
AntiVirus: Windows Defender (both ON), AVG-free (both ON)

AVG scans daily at noon on both machines. The Sony's odd "alert" behavior doesn't occur on mine.  AVG scans have fairly clean results (warnings only, which I assume are for tracking cookies.)

My internet habits are fairly restricted: 8 to 10 "safe" sites.  She spends time on Pogo.com and collects recipes.  We both email (Yah__) and play the occasional amusing *.wmv video capture friends send to us.

Anyone familiar with this behavior?  Is something venomous going on?

Thanks...

[evilfantasy]

Both laptops:
Firewall: Comodo (mine), Windows Live OneCare (hers)
AntiVirus: Windows Defender (both ON), AVG-free (both ON)

The real-time protection of two antivirus programs may conflict with each other and cause the following:

1) False Alarms: When the anti virus software tells you that your PC has a virus when it actually doesn't.
2) Conflicts: Your system may lock up due to both products attempting to access the same file at the same time.
3) Performance: More that one antivirus will cause your PC to become slow and it may even crash or blue screen.

Uninstall OneCare or AVG and see if it stops. You should never run two antivirus or firewalls at the same time.