I have an assembly which has two configurations. I am running a couple of Linear Dynamic Vibration Studies relative to each configuration and am finding that occasionally after a re-open the last part within the simulation study gets dropped off and as a result the mesh and results are not up to date.? I'm running SolidWorks 2018 SP2.0 with Simulation Premium. Any suggestions? I have taken the results that I need for analysis into excel when the mesh and results were up to date so I don't need a solution immediately, however the simulations that I am running have large solve times so it is a pain to run them again.