With my Nikon D70 the err message is displayed while out of automatic?

When I shoot in automatic mode and some of the others (like portrait) the camera works fine. However when I'm in manual and of the other modes it takes the picture but says err on the screen and the picture is not saved to the camera. Does anyone know how to fix the err message. I'm running firmware a 1.01 and b 1.02 and shoot with a nikon 18-55mm lens

* Ultra-compact 3x zoom lens designed exclusively for use with Nikon Digital SLR models
* 18-55mm focal length
* f3.5-5.6 maximum aperture
* 7 elements in 5 groups; 1 extra-low dispersion element and 1 hybrid aspherical element
* Silent Wave Motor