Thanks Erwin.

Before seeing your post I impatiently took the simple route in File Explorer of dragging all the D:\My Music folders to D:\Music and then removing the duplicates and tidying up a bit. I've so far done only a cursory check but think this will allow me to finish the immediate task (by this evening's deadline).

A puzzling side issue. Yesterday my MM tray icon was opening 4.1. That's my preference at the moment, despite installing 5.02 a few weeks ago. (I like my old MM's familiar distinct window borders, for one thing; and although I haven't time at the moment to check methodically I also suspect version 5.02 has not retained all my settings.) However, strangely, when I returned to my PC this morning to try your suggestions I found that the MM icon had changed (to a slightly smaller one) and it opened version 5.02. Which BTW doesn't have Tools>Options...Library...[b]FileMonitor[/b]; that's accessible in both version with File > Add/Rescan Folders (or the Insert key shortcut).

Any ideas how it could change like that?

(Just seen your reply Lowlander, thanks, as I was about to hit Submit.)

You can Cut & Paste in the Media Tree itself. So you can move folders this way in the Location sub-node or the My Computer node.

Another possibility in MM4:
Step 1) Tools>Options...Library...FileMonitor .... Activate Folder "MyMusic"... Scan continuosly
Step 2) After OK the folder will be scanned.
Step 3) MM4 restart
Step 4) Select from MediaTree: ... "Music" >Location ... click on Folder "MyMusic"
Step 5) Select all songs
Step 6) Context menu button "Send to" ... Folder (Move) ... "Music"

A few hundred songs, that only takes a few minutes.

But as that's at [u]track[/u] level, and most of the folders (artists) have just one track, it will be a tedious process! No quicker way at folder level?

Thanks, I'll do that.

There is no issue moving them, but I'd recommend using MediaMonkey to move the files: https://www.mediamonkey.com/wiki/WebHelp:Changing_Filenames/4.0 This way the database is updated with the new file locations.

It's taken me a year or so to notice this so I expect it has an embarrassingly obvious cause!

For several decades, on successive PCs and Windows operating systems, I've kept my music in [b]D:\Music[/b]. It currently contains about 12,000 tracks and is 24 GB in size. But I've just noticed that that I have a few hundred in another folder, [b]D:\My Music[/b]. Not sure without further study how they got there, although FWIW I see none with a Date Created before 2020. I suspect I've changed a setting in MM. Anyway, is there any reason why I shouldn't simply copy them across to D:\Music?

Any tips on the easiest way to do so without duplication please? IOW with the least manual intervention?

Win 10 Version 20H2 (OS Build 19042.1586), currently using my familiar MM 4.1.13.1919 (Gold)