Email attachments and contents vanish when I save email to "on my mac", Microsoft Exchanger server, only header remains
Emails arrive at Microsoft Exchange server. I retrieve them using Mac Mail (on MacBook Pro, or iPhone). In the past I could simply drag them into the folders I created under "On My Mac" for easy recovery. Recently that stopped working in that when moving emails which include and attachment, the email appears in my folder, but the attachment and text have vanished. Please Help Me with this.
I have tried 'rebuilding' some of the folders, but it doesn't seem to help and I am afraid of loosing what I have. I have a back up of the computer (now approaching 50 days old) from before this problem started, but I'm not sure if this will help me or just lose me the activity in the intervening period.
2022 Mandy's MacBook Pro