Error on nikon d 70s
I occasionally get an ERR on my D-90 and it seems to happen for different reasons. Sometimes, it's kinda hard to figure out and it's hard to clear as well. One way I get it, is if I try to shoot without the SD card installed. I've also gotten it when I've been in manual mode and the settings were so far off that the camera could not function as set. So far, I've always been able to clear the ERR by turning the camera on and off if nothing else works.
I went to the D-90 manual and could find nothing about error messages nor could I find any reference to error messages in the table of contents. I happened upon what Nikon calls a Q&A index in the front of the book before the main index. Down in the list of questions, there was one which said "What do these warnings mean?" then a box which said error message and a reference to page 255 in the back of the book. I went to page 255 it showed a multitude of messages of different types but only one ERR.
The explanation was that this indicated a "camera malfunction" and to clear it, you are supposed to release the shutter. In the next box, it said that if this condition persists or occurs frequently you should contact Nikon Tech support.
Interestingly, when I get this message, the shutter will not release and I have to turn the camera off to make it release. When I turn it off and back on the error message has clear.
I hope this information helps with your D-70.
Incidentally, I've found the people at Nikon tech support to be very friendly and helpful.