http://www.nikonchat.com/coolpix-4200/
Some SD cards don’t work on my digital camera?
I’ve Nikon Coolpix 4200, and I just bought Sandisk 4gb SD card to replace PNY 128mb. It simply won’t work and the screen says “This cannot be used”
Why is that? How do I know which SD card work? I thought they were all the same except for the capacity 
anything above 2gb is usually a SDHC card. the HC means high capacity and is a different format then the regular SD. if your camera doesnt say it is SDHC compatible then it wont be able to read an SDHC card so you might just have to stick with a 2gb or lower.
David Blaine – Dive of Death – The Truth from theJJB.com
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