MS LiveOneCare,MpEng.exe CPU usage 100%

Every now and then my notebook Functions/Pointer etc. will stall/hesitate. Task manager shows mpeng.exe cpu operating at 100%.
I switched off my network/internet.
Diabled webroot spy sweeper.
Disabled Live One Care anti-virus.
Disabled Live One Care anti-spyware, then disabled One Care anti-virus.
CPU usage remained extremely high, untill the final step...Disabled Live One Care Firewall Defender. The CPU usage dropped to zero levels.
Then, enabled all of the above, including OneCare Defender firewall and the mpeng.exe cpu usage remained very low and has remained low for two days.
Its like mpeng.exe was locked up, utilizing high CPU usage. Therefore stalling my entire computer.
Since two days ago, the only time mpeng.exe demanded high cpu usage again was during a LiveOneCare anti-virus scan, and get this...The only time mpeng.exe cpu usage went high during the scan, was when it was scanning microsoft products such as Works, Office or ms files. The scan boged down and the scan was extremenly slow.
But after the scan, cpu usage went down to normal levels.
This is a BIG problem at the Microsoft LiveOneCare help site. People , with subcriptions, are removing LiveOneCare from their computers.
Computer stalling has happened on my computer before. Especially since the insallation of OneCare and the upgrade to IE7,which I don't use IE7anymore. So I just rebooted to get back to normal. I once suspected infections, but not so sure anymore. Not since I am aware of the MpEng.exe problem.
sutterkane
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