Using mailcall in Unform, is it possible to set ‘Request a delivery receipt’ or ‘Request a read receipt’ as in MS Outlook?



Yes it can, but how you do it depends on exactly how you are emailing: deliver command, email command, email function, or direct calls to mailcall.  The thing that needs to be done is to add an 'other header' value:

"Disposition-Notification-To: emailaddress" 


If you are using direct calls to mailcall, here is an article about it:

Note that this simply requests  that the recipient acknowledge receipt.  It does not require them to do so.