Hi try this, first back up your pics on your pc. Then you are going to format your sd card, it is
sd isn´t it? as you cannot use sdhc.
1.check the lock switch on the memory card (make sure it is in the up position...unlocked)
2.With the camera off, insert the memory card.
Turn the [Mode dial] to the position that has the [Wrench Icon]
Turn the camera on
The Setup menu should be displayed
Use the down Arrow to select [Format]
Use the up or down Arrow to select [OK]
Press the OK button
The formatting process will begin. Do not disturb the camera until complete.
That might help let me know.
I found this answer on the web.