Windows Explorer shows 14 more folders in the folder C:>Users>Whitey than Opus shows. I am particularly, at this time, looking for the folder C:>Users>Whitey>AppData. No problem in Explorer, why not in Opus?
You probably have Opus configured not to show hidden files/folders.
You can toggle it under Preferences / Folders / Folder Display / Hide hidden files or via the similar option in the menu, near the top-right of the default toolbars, which starts with Folder Options, Folder Formats, Folder Tabs...
Thank you - works fine now.