I am trying to add an option by which users can register by their emails to receive updates whenever there is a change in the products information. By searching different options, found SMTP email module to download from App store, but it is not working with the Mendix version I am using. Any advice on how to fix it, or whether there is a better option?
You can import this module in 7.23.x, export the App store modules → SMTPEmailModule and then import it to your 8.5.1 module.
Another option is to use app Email module with templates.