Can you open the drawing for view only? if yes then suppress all the components in the assembly and then open the drawing for real. if that works unsuppress the components one at a time opening the drawing after each unsuppress. Hopefully this will point you to the solution.
Hi Solid Air,
Thanks for your reply, i try it to open in view only unfortunately nothing has change, still i was not able to determine the cause. i don't have any choice but to do it from the start. and what i did is, i save the drawing in one file each part instead of adding sheets to drawing.
thanks again, sorry for the late reply...