We have a piece of software that uses the Persits ASP Email software to transmit SMTP e-mail. This worked fine on Windows NT and Windows 95. We have upgraded our client operating systems to Windows 2000 and now when we try and send an SMTP e-mail from these machines we get a "Connection Refused" error. We have also tried to use the Microsoft CDO for Windows 2000 DLL and using this we get a "The transport failed to connect to the server" error. The SMTP Server is up and can be pinged.