Problem in MRP run

Dear PP gurus,

I am running MRP first time for a plant .I have two level BOM. I am using 40 strategy for FG material.During the planning run i have selected processing key as NEUPL ( regenerative planning).

Once i run MRP , system is creating planed orders for FG and purchage requisitions for safety stock of rawmaterials. system is not exploding the BOM for MRP.And system is not creating any planning praposals for any materials(at least dependent requirements).And my bom's stastus is 1.

While doing standard cost estimation , BOM is exploded with out any problem.

can any body can suggest me how to resolve this problem.