Microsoft Security Essentials Start Option

 The settings option "Start the scheduled scan when my PC is on but not in use" is ambiguous.
I have a laptop running Vista Premium with his option ticked. The scan does start at the scheduled time.
On the other hand, I have a desktop running Vista Ultimate where the scan does not start at the scheduled time unless this option is un-ticked.
The desk top has back ground programs such as Samsung Link.exe and All share framework DMS running that the laptop does not have running.
Do programs such as these qualify the computer as being  "In Use" ?
Thanks

1. Did you first install MSE on 13 January 2015?

• At least one of your previous threads suggests that AVG Internet Security and MSE were both installed at one point. [1]
  
  
• It'd be most unusual for a Dell computer purchased in 2008 (let alone 2015) to come without a Norton or a McAfee free-trial preinstalled. I suspect that may be the primary cause of your many ongoing problems over the years, Frank.

2. Flash Player v11.3.300.257 is subject to thousands of security vulnerabilities! Can you successfully upgrade to Flash Player v17.0.0.134 (or higher) by opening Internet Explorer ONLY (not Firefox) to this page? => http://www.adobe.com/go/getflash

• BEWARE any pre-checked options to "drive-by" install unwanted, third-party software (e.g., Google Toolbar; Google Chrome)!

3. You never ran AVG PC TuneUp when AVG Internet Security was installed, is that correct?
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[1] http://answers.microsoft.com/thread/61b4ee35-b57c-4b29-bff0-3f95bb2f7c0c