Problem with IIS

I have had some serious trolls on my forums and would like to revert to the old way of email notification but every time I switch it on new would be members do not get their activation email. I have had a programmer look at this and he says that my server no longer supports IIS and I need to use .net mail. I do not know anything about this and have no funds to be able to pay someone to do it. Is there a webwizz add on for this?
Queensah