Blanket PO Approval

[SanjayS]

Hi Everyone..
What are the mandatory settings to be followed for the Blanket Purchase order for an OSP item to be approved?
I have defined the OSP item with list price and checked the Unit Type (assembly)and also enabled the osp tab.
I have defined the employee with job and position and as a buyer.
Is the Dept location mandatory for the approval of the Blanket PO?