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MultiMediaCard (MMC) Icon Appears Instead of a Secure Digital (SD) Card Icon
http://www.vistaarticles.com/articles/268/1/MultiMediaCard-%28MMC%29-Icon-Appears-Instead-of-a-Secure-Digital-%28SD%29-Card-Icon
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Published on 12/10/2006
 
When you connect a MultiMediaCard (MMC) to a computer that is running Windows Vista or Microsoft Windows XP, the device appears in Windows Explorer with a Secure Digital (SD) Card icon instead of with a MultiMediaCard (MMC) icon.

MultiMediaCard (MMC) Icon Appears Instead of a Secure Digital (SD) Card Icon
No steps are required to resolve this problem. The device will work correctly. The problem only affects how the icon for the device appears in Windows Explorer.