ModEdit;
Try it out before posting in the thread.
Tying the thread to ticket #18990: Catalina host with Win 10 VM crashes
I Just upgraded to Catalina 10.15 and did the steps described with the same results using (VirtualBox-6.0.12-133076-OSX). The VirtualBox App runs fine but the Virtual Machine keeps throwing the NS_Error_Failure when I try to launch the virtual machine that previously worked.