My D700 is about three year old and has never had any problems. The numbers which it gives to the individual photos had got up to about 9990. But today I noticed that the numbering had restarted at 0001, and as a result of photos taken today has got up to 0044. Is this supposed to happen? It doesn't sound right to me, as presumably it means that the first 999 numbers will become duplicated... and so on!