Modified library file.

Hi,

I took a library part (3/4-16 bolt) and modified it to my purpose. The problem I'm running into is that the part will not stay in the asm that it is mated in. Everytime I pull up the asm the toolbox replaces the file with the bolt out of the library. There must still be so kind of "link" in there. Does anyone know how to find this link to stop the library from replacing the file? I can replace the file back into the asm and all of the mate correct themselves. But that gets old.

SolidworksToolbox