No idea if this links to the reply by JeffYang-MSFT to my original question. (Amazon do things much mire professionally.)
The message I get (admittedly not every time) is "Cannot move the item. The operation cannot be performed because the message has been changed."
There is no error number!
My Outlook interfaces using IMAP to a Yahoo server.
Why some messages return this I have no idea. If it helps, your email to me is one that I cannot move.
Despite no error message, it cannot be difficult to identify the criteria that spawns this specific message; and rules that apply in Inbox yet not in Trash.
The only thing that has changed is the status - to read from unread.
I will not close this thread until you provide a software "fix", because it's a software / design error.