HA-HA!!! Solved it! It is because of stupid bugged Windows Store version.
Uninstall your application. Then download the "Traditional win32" .exe file from here: https://www.enpass.io/downloads/
After the installation of this package everything began to work!
P.S. Just for the case I uninstalled the browser plugin also before the installation and rebooted the system
I'm having the same issue! Android applications work fine though. Can't access any passwords from the desktop. Reloading PC/browser, reinstalling the app, launching the app in admin mode do not help. The app also can't read the backup file with the error 995