Same issue. I have multiple monitors. Deleting geometry fixed it!
oftebro wrote: ↑Thu Mar 26, 2020 11:31 amI tried the RegEdit and deleting all the Geometry items and it didn't work for me.
I got this info from Simplify Support. Worked great!!
"Thank you for your e-mail. I am happy to help.
Could you please try navigating to your Simplify3D working directory (likely at C:/Users/%USERNAME%/AppData/Local/Simplify3D/S3D-Software) and deleting the savedState.factory file? This is what loads the previous state when launching the program, so if something too large was saved, or if the file got corrupted, this could cause the failure to launch that you are seeing"
Thanks to the community and Simplify Support!!