Has anyone had any luck using ‘Yahoo SMTP’ for the DNN SMTP email server?
If so, would you be so kind to provide info on how to configure DNN correctly for it to work.

Are you hosting with Yahoo?  I know Gmail works as a third party server but I'm not certain Yahoo allows you to do the same.

Jeff

I recently shifted my site to gmail.  I'm using the app engine with the full domain, but the same instructions apply whether you have a @gmail or @example.com domain.

What I ended up doing was creating a completely new email account, just for smtp services.  This account is 'notifications'.  I then configured the gmail smtp server, put in the username and password, and checked 'use ssl'.  It works fine.  I also added a vacation reply into the notifications account, so that if anyone replies to the notifications emails sent from the site, they get an auto-reply telling them that nobody is reading the emails and suggests some links to try instead.  This is to try and get people to use the correct channels on the site to get the best type of response.  I find anyone with a working email address will hit 'reply' before they do anything else and this can create a lot of time-sapping emails to point people to the easily-found parts of your site.

I don't know about Yahoo, but gmail definitely lets you use their server for smtp.  Just look up the details on how to configure the account for an email client - the information is the same even though it is written for outlook and other clients.  You just need the smtp server, username, password and the fact that it uses ssl for the authentication.