My guess is that you got a version of the tool via Windows Update. It is a tool runs in the background once a month to help keep your computer free of infections.
You can read more about it here - http://www.microsoft.com/security/malwareremove/default.aspx.
Cheers,
Cassandra
Kb890830
MS says this tool runs once a month in the back ground.
How?
Is this a scheduled task?
If so....which task is scheduling it?
I've never seen it run.

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