Final update, it worked on the production server!! so now our forum is working properly sending emails the Linux way on a Windows Server OS, quite nice I would say, just as a side note our forum is actually really small in number of users, as it is an internal forum, so I can't assure this setup will work out to other forum's expectations or needs, also I would like to add that this shouldn't be the way to do it on Windows as it is kind of a weird way to handle it so in later versions it would be nice to see it reworked or polished for Windows environments (especially because it looks like the program used to simulate sendmail on Windows is no longer receiving maintenance).
@Gaurav-Grv-Robinson It looks like NodeBB uses the nodemailer package under the covers, but the UI may only present SMTP transport options.
Your best bet is to use an SMTP server that's configured to listen/login/relay email on your behalf, this is a little different than a mail spooling system that in the end may relay, or otherwise send directly. If you have an inbound mail server that also has smtp for outbound, use that.
I tend to just use SendGrid (hosted SaaS mail delivery) for my outbound emails, because delivery rates come out much better. There are other services, and depending on where you are hosting, they may offer one.