WIA object returns nothing in windows XP

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Silverlight5

I have used vs2010 and silverlight5. I can able to access scanner through WIA Object on windows 7(32 and 64bit) machine. But WIA object returns nothing on windows XP(32 and 64bit) machine.
When i going to create object like AutomationFactory.CreateObject("WIA.CommonDialog")), i got error as

"No object was found registered for specified ProgID"

Is there any different between windows XP and windows 7?
(0r)
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My code is,

try 
{ 
using (dynamic CommonDialog = AutomationFactory.CreateObject("WIA.CommonDialog")) 
{ 
dynamic imageFile = CommonDialog.ShowAcquireImage();
} 
}

Thanks in advance