Echostar Dvr 700 HD after change not found?what data system is using=?

Turok

Hello !
last week ,i want to replace the old noise 40 gb hd,into a new modell with 250 gb,this if i remeber right,is th maximum size,what i can use in this receiver,iam using segate hd,but after formating on fat 32,nothing will hapens,when i put back to dvr 7000,like no hd is conected,in the menu it self ,the point formating the hd ,is complitly missing,and not avalible to select!

when i put the orginal hd,into an external usb hd box,then it will be also not recogneized ,and i dont see any directory structure,´what datasystem is using in orginal,maybe there are more then one hiden partions on the orginal hd,where i need a special programm to see it?
thx for your help!