Hello,
Prior to org-mode version 9.0 I was able to use the default program for
a file type on Windows 10 with the following setting:

(setq org-file-apps (list (cons t (list 'w32-shell-execute "open" 'file))))

However, now (currently my version of org mode is 9.1.9) nothing I try
works, including the instructions provided in the release notes of version
9.0.

Can someone, please, provide me with the correct value of org-file-apps
to use if I want a click on a file link to result in a call of the Windows
10 default app.

Much obliged.

bostjanv