>Did you put a different card into the D800, possibly one that
>had not been formatted in the D800. If so, the body will
>pickup with the last file numbers on a used card, I have been
>told.
>
>
The exact same thing happened to my new D800 camera when I sent it in to Nikon to have my focus fixed. When it returned, my file numbers had increased by 1500. Evidently, when the camera was serviced, the camera picked up count from the CF card they had used. ~There is a reset on file numbering on the D800 that can start it over again @ 1.~