Sansa View 16GB micro SDHC Card

I need some help. I have a Sansa View 16GB MP3 Player. I bought an 16GB MIcro SDHC card and inserted it into the player and it was recognized. Previously I had an 8GB card that I copied the music from and put it on my hard drive. After inserting the new 16GB card and having it recognzed by Windows Media Player, I copied the music from my hard drive on to the 16GB card. Once this was done Windows Media Player refuse to recognize the new card. Even using Windows Explore, I can not read the contents on the card because it is not recognized as being in the MP3 player. How can I access this card and get windows to recognize it again?