Fusion quits after splash screen

Fusion standalone hasn't been working for me for some time.
Did a clean install of version 20. When I try to start it, splashscreen shows and then closes.
No messages or anything. It was the same with version 19.
any tips?
Windows 10, Nvidia 4090 with studio driver

You are probably left with the task of searching through the Windows Event Viewer for clues. Right click on My Computer and choose Manage. Then double click on the various Administrative Events etc. At least that's one way that it used to be accessed but it may have changed.
If everything else is running smoothly, you could clear the various logs and then try to start Fusion, they are only logs that you probably never look at unless there is a problem, what could possibly go wrong?
Oh and plug ins, if you added any plug ins they quite often are the cause of start up problems.

thanks birdseye, didn't feel much like troubleshooting, instead I installed in Linux where it works fine. Gotta get used to Linux, its more relevant than ever.

It's going to be something specific on your machine causing the issue, as if this were a regular issue on Windows, thousands of others would have reported it.
Best I can offer is to do a full uninstall of Fusion Studio using Fusion's own uninstaller (and Resolve if you have that installed), then run a scan on your system for any scraps of installed files or preferences associated with Fusion / Resolve, blow them away, reboot and try again.