2,235 votesNeal Davies commented
I hate to have to do MSFT's job but you have a duplicate item
"Option to Reply to an email with attachments included in Microsoft Outlook 2016" has 384 votes
Add them up and that is over 1000 votes, a popular item !
Please consolidate your work.
ThxNeal Davies commented
Agree with J C. For invoice payment collections, respond to the last e-mail, attach your supporting documents ( invoices ...). This is an annoying, error prone 2 step process now. A "reply all + attachments" would be a dandy time saving feature.