Scrivener won't open

I have two machines: a desktop, which I use daily, and a netbook, which is used intermittently. I have Scrivener installed on both, and my data files reside on Dropbox.

The desktop runs Windows 10 Home v.1909.

Today when I tried to open Scrivener, it tries to open, briefly displaying a white screen with the filename of my project in the upper taskbar–then it quickly closes. I’ve tried rebooting, but it makes no difference.

I’ve tried clicking on Scrivener from File Explorer, but get the same result as clicking on the icon on my desktop or taskbar.

I checked the netbook. When I opened Scrivener, I got a message: “Project Already Open …seems to be in use by another program…” Even after shutting down the desktop, I get this message on the netbook. The message offers me the option to make a copy of my files, or continue, or cancel. I selected continue. The program looked normal, the screen properly displaying my working files, but I checked the version number and closed out immediately.

The netbook is running Scrivener v. I can’t check the desktop to see the version of Scrivener there, but it should be the most up-to-date version.

24 hours later, I gave Scrivener a try and it opened just fine.

I don’t understand why it did not work yesterday or why it’s working now, but I’m relieved to have it back.