Cumulus Support

Looking at your script, and reading how you are still trying to get it right, I still believe my MX updating approach using http://www.codesector.com/teracopy is easier, quicker, simpler, and safer. But, your approach might be more fun for you, and suit you.
My tool replaces just the new files and it verifies each file copied so I update quickly and reliably.

As you can see on the linked page it handles locked files and works unattended once you start it by clicking on the unzipped folder just as you would with a normal windows (or mac) copy.
Settings like copy only updated files and verify files can be set up as defaults. This particular tool can't do FTP transfers for those installing MX on another device, but there are other similar tools to copy only updated files with FTP option.

I don't need to look at the list of files in the release announcement, I don't worry if the release announcement content has typos or missing details. In your approach, you could make typos or other errors in creating that list of files. My update is finished in less time than it takes you to read the release announcement, type in your list of files, and set your script off.


I always download to same directory and always overwrite CumulusMX (although I do have a backup of previous installation).

I am not used to serverpath referencing in DOS so I do not understand where the dir listing begins eg. in terms of the target destination.
D:dir and D:\dir are both valid.
... but why wasn't your destination S:\CumulusMX ?

Note: limitation of using xcopy - destination must be a different disk to the one containing the files to be copied'

If you change It may make the o/p display a little more correct.
... and to get rid of overwrite existing prompts add /y flag ... anythiong else you're on your own ...