Hope this is in the right section, if not please move it admin. right so i got a sb-600 new from amazon a week ago for my Nikon D200 and from the off set it has worked brilliantly up un-till tuesday. where it just stopped working. its got all the settings and stuff on the back but its just not firing or making that humming noise when the flash is meant to be recharging i hope you know what i mean. also the 'ready' light on the back of the flashgun does not light up any more tho flashes a few times after i take a picture, even know the flash its self does not fire. well after it goes on stand by it says 'bat' which according to the manual is the battery, at the time of starting i had a set of engergiser batteries in, non rechargable 2500's so went out and buy my self a set of rechargable 2500 engergiser's wait till they have charged up and still the same problem the flash shows all the writing and the light works on the flash, even the auto zoom bit works on the flash but its just not charging up and flashing. and the same 'bat' message is coming up when it goes on standby. so maybe thinking its the batterys again i buy a set of duracell ultra AA's and still the same problem. now ive tried resetting the camera, and looking in the trouble shooting part of the manual, tried turning the standby function off through the buttons on the back of the flash, i have even tried a few settings on my D200 and reset all the settings on that, but still no joy. i have tried different lens also, to see if that makes a button of difference. i may try and see if it works on my friends D50 nikon when i see him at the weekend. but i doubt that will make a diffrence. so now im a bit stumpt, all i can think of is something has went in the inside to think what ever batteries i put in are low power or the actual bulb has went, but surely not after a few days of use and possably 150 pics taken. if any one can help me that would be so great.