Since upgrading from El Cap to High Sierra I've had trouble deleting attachments to mail, both sent and received. In the case of sent mail, the mail display (Classic layout) doesn't even ship the paper clip icon on mail with attachments, and the "Remove Attachments" command on the Message menu is grayed out.
I've not been able to find any discussion about this problem, but I have found a hack-around from when this problem popped up in ML that does appear to work:
http://nohejl.name/2012/03/03/remove-attachments-workaround-for-apple-mail/
Hope Apple decides to fix this, and other, Mail problems soon.
I've not been able to find any discussion about this problem, but I have found a hack-around from when this problem popped up in ML that does appear to work:
http://nohejl.name/2012/03/03/remove-attachments-workaround-for-apple-mail/
Hope Apple decides to fix this, and other, Mail problems soon.