Installer brings up blank window and nothing happens

I’ve tried Googling for results on this problem, but unfortunately all I find are years-old threads that don’t provide any of the solutions I need.

When Scrivener prompted me to update, every time I got to the installation part it just brought up a blank window and nothing else. Feeling a little frustrated, I tried uninstalling so I could reinstall it again, only for the uninstaller to do nothing, and so I had to uninstall it with a program wiper…but now not even the regular installer from scratch will work, since it still brings up a blank window, and now I can’t use Scrivener at all.

I’ve tried:
-Running the installer from an external hard drive, and from a USB drive;
-Running as admin;
-Compatibility mode;
-Safe mode;
-Whitelisting the installer in my antivirus;
-Restarting the computer;
-Trying to install an older version instead…

…but nothing works, it’s still just an empty blank window.