Help~~ the belt fall off

Most turntables have the belt wrapped around the bottom of the turntable platter, and then around the motor. You'll have to remove the rubber mat, to expose some holes on the platter, where you can squeeze your fingers in to pinch/wrap the belt around the motor shaft - generally on the lower left side. You can't miss it.

Also, for future reference, here is the operating manual for your unit, and it has instructions on replacement the belt - it is on page 6:

http://usa.denon.com/DP29F_DFU_ownersman...