Hi Patrick,
Deleting the .sta file did not help. Maybe it's not SE. I think that this VM may have issues. I don't use it a lot but I have had it around for a while. I got some "cannot delete, READ ONLY" issues the other when I tried to delete files. I have checked the SSD in the Win10 host OS and it is OK. So, it has to be internal to the Linux VM, maybe the kernel got corrupted.
I am going to import the VM from the original .ova file and reinstall SE on that.