CDONTS.NewMail issue

Our web application runs on windows nt and for some reason, our IT staff is no longer getting the emails from the web application.  How it works is that a user would type in information from a form, and when he/she hits the submit button, it will send an email to our IT department with the information that the user typed in.  We did not change any code.  We're not using our exchange server to do this.  I tried unregistering and registering the CDonts.dll in the server, but it did not solve the problem.  Any ideas why this is happening?
 
Randy