Folder appears empty in Windows Explorer but I can see directories and files in WDMyCloud app

This morning I mapped a network drive to Windows Explorer and could see the contents of all shared folder. Tonight I can see the contents of some shared folders, but others are empty: Windows Explorer says “This folder is empty”, but I know it’s not.
Also, not all folders are visible using Windows Explorer.
My firmware was updated this morning.

What happens if you disconnect all shares after rebooting the unit? Is this happening on all computers?