CHR Error on Nikon N90?

I recently got Nikon D90 and i got this error a couple of times and every time when i switched off the camera and back on it was gone. Can somebody tell me about this error and why does it occur.

If i recall correctly that is a memory card error. Try to reformat the memory card in the camera several times, and also outside of the camera on a computer. That fixed it the last time that i encountered what i think was this error.

If that doesn't do it, a new memory card may be due.

Change the memory card.