Occasionally we open an assembly and it looks like below, where only some of the parts have loaded graphically, but they are in the Design Tree. The only two options we have been able to find to show all of the parts is to A) Suppress and unspress the parts or B) Reload the whole assembly. You will notice that there are not that many parts in the assembly and they are not set to LightWeight.
We have also seen a person open a part from the assembly and then go back to the assembly, the part will have graphically disappeared. We are running off of a server that goes through several switches, but even those closer to the server have the same issues. About the only thing I can think of is that we are not using PDM and we share a lot of assemblies to put into other higher assemblies, which could possibly cause problems? This problem happens enough to be quite a pain, but not repeatable. If you have any ideas or suggestions it would be much appreciated.