OR usu there is a .dll or .ocx installed for every app.
Enter VBE, Alt-F11,
menu, tools, references
check mark TLS mail, (or similar object library)
then use the code below, but replace OUTLOOK objects with your TLS.
It may or may not work.
call Email1(sTo, sSubj, sBody)
Public Function Email1(ByVal pvTo, ByVal pvSubj, ByVal pvBody, Optional ByVal pvFile) As Boolean
Dim oApp As Outlook.Application
Dim oMail As Outlook.MailItem
On Error GoTo ErrMail
'NOTE : YOU MUST HAVE THE OUTLOOK REFERENCE CHECKED IN VBE; ctl-G, menu,tools, references, Microsoft Outlook XX Object library
Set oApp = CreateObject("Outlook.Application")
Set oMail = oApp.createitem(olMailItem)
.To = pvTo
.Subject = pvSubj
If Not IsNull(pvBody) Then .Body = pvBody
If Not IsMissing(pvFile) Then .Attachments.Add pvFile, olByValue, 1
'.Save 'draft, we are NOT sending...we save as draft
Email1 = True
Set oMail = Nothing
Set oApp = Nothing
MsgBox Err.Description, vbCritical, Err
First, you should find out what protocol(s) your provider supports.
The recommend namespace for email is System.Net.Mail. However, as far as I know, this supports only explicit SSL/TLS with the STARTTLS command.
This might have changed with .Net 4.6 and later because there where many SSL/TLS enhancements included.
You could also use System.Web.Mail. This namespace supports implicit and explicit SSL/TLS. However, it is marked as deprecated but still work in all current versions of .Net Framework.
In any case, I would suggest you wrap your email code in a custom abstraction layer to easily change it later if requirements, availability and/or capabilities of the used email component change.