Tool box issue in assembly

Hello There,

I used tool box part in an assembly and i opened that part (let us say screw) and clicked on FILE >> SAVE AS>> and i selected specific file name(6-32 pan head 1" screw) for it. When i opened assembly tool box parts are named as 6-32..... and later on i saved it and closed it. But when i opened it on the next day it is showing as part in tool box but not with part file 6-32 pan head 1" screw.....

I don't know why it is catching up tool box part everytime instead of custom part. I even deleted all configurations in 6-32 pan head screw file but it is still doing the same thing. BTW  i am using SW2012 sp0.

Thank You in advance.

RAM

SolidworksToolbox