Desired Outcome Goal:

Sending out email notices in HTML rather than plain text.
I am aware that at least in version 18 and before it was only possible to send the email as an HTML email as an attachment. Has this changed?
 

Procedure:

Yes, this is possible starting with Aleph version 21.

[From the Aleph 21 Release Notes]:

HTML in e-Mail
Purpose of Enhancement
It is now possible to send e-mails to patrons, vendors, and partners with formatted HTML in the body of the e-mail.

The HTML Body Only option has been added to the Mail Attachment drop?down list. Selecting it causes e-mail to be sent with formatted HTML inside the body of the e?mail. The related HTML is built according to the defined XSL files, which are located under the form_LNG directory.

For more information, refer to the "Sending Attachments in E-mail Messages" section of the "Aleph 21 System Librarian’ s Guide - Printing".

xxx50/tab/pc_tab_exp_field.lng:
..
!*
PLAIN-HTML L Attachment Only H
PLAIN-HTML L Email Body Only P
PLAIN-HTML L Attachment and Email Body B
PLAIN-HTML L HTML Body Only L << see new option here
!*

[From the header of alephe/tab/tab/tab100]:

!# PLAIN-ONLY
!# Values:Y N H Default: N
!# Type: Text; Max Length: 01
!# tab100 of library: No; tab100_<server_type>: No.
!
! This variable enables shutting down the option to send
! email letters with an attachment. Note that it is configurable
! only in the alephe table.
! Y = Do not send an email attachment, no matter how the patron
! or vendor records are defined. Only plain text in the email
! body will be sent.
! N = Send email attachments depending on how the patron
! or vendor records are defined.
! H = Do not send an email attachment, no matter how the patron << see new option here
! or vendor records are defined. Only HTML format in the email
! body will be sent.

• Article last edited: 14-Dec-2016