I've just come across this problem with version 3.6.0. Yesterday Cura asked me to update and I did. I did several prints (on Creality CR10) with this version. This morning I started the PC then tried to open an STL file and nothing happened: there were several Cura instances in task manager, but no GUI.
After finding this thread, I did the compatibility trouble shooter and Cura does open when I choose to Test, so at least I have a workaround now.
Windows 10 is build 17134.471. Display adapter is Intel HD Graphics 630 driver 25.20.100.6471. Avast free anti virus 18.8.2356.
I've been using Cura for about 6 months with no issues until now. It is a great piece of software. I assume some weird combination of Windows or driver updates is to blame. I hope the problem gets fixed soon.
Merry Christmas!
