I discovered that some model is not able to be repaired. When i import the model to preform v2.16, it tells me to repair the model and after clicking repair, preform just did not load at all. This issue happens in Window 10, and when i switch to my Macbook Pro, the issue disappear.
I’ve had this happen to me a few times in the past week. I load Preform on a different computer than my modeling software that all uses a shared network folder. I just re-upload my stl files to the network folder and it works for me.
I have had this issue as well. It has either been too many polys or it was a network issue. In the event of a network problem just download the file to that computer instead of pulling it from another location. I just dump it on my desktop and it stops being a problem.