In Assembly, sometimes I open subassembly and try to select a part to delete it but as soon as i select the part, it creates a copy of it and puts it in assembly. It does not happens everytime but many times. Can anyone help?
I guess you are reffereing to interpart relationship. I have not used any special command like interpart link. Its just simple assembly of subassembies using command assemble.
If I'm correct, I also see this behaviour occasionally.
My interpretation of the the problem is - in an assembly, selecting a part/assembly in pathfinder adds a new instance of the part/assembly, instead of just highlighting it (as if you grabbed it in pathfinder and dragged it into the modelling window, or doble-clicked on it)
I don't think it has anything to do with part copies.
I've mostly seen it on big assemblies, and it's almost like the single click on pathfinder is being iterpreted as a double-click.
Is it happening in large assemblies?