D800 shutter misfire with "ERR".
Only time 've seen an ERR was card related. First was out of the box new with a Kingston CF card. Got rid of it and put in a Sandisk (one recommened out of the book) and it went away. The Kingston was NR/Not listed in the owner's book.
Second was a new Sandisk 16GB Extreme card (above was a 32GB Sandisk CF, fwiw) from Best Buy and it threw out the ERR too on formatting right out of the package. I could format it in Windows 7 using a reader, just the camera didn't want to do it for some reason. Took it back and exchanged it for another one and the ERR went away.
Occasionally my display will remain dark when I hit the review/playback button. Don't know why, but a second shot and the display will come back on and work after the "Writing" green light finishes. Maybe card or some internal firmware bug. No big issue as the shots are all there.
I need to try and use some Lexar CF cards next as I've had some Sandisk go back under warranty for read/write errors (2 CF and 2 SD cards so far, both Extremes.).