Get port 25 in use by other app error

After install on win 2000 pro machine, get port 25 in use and will not protect stmp mail. How do I fix this?

Set avast4.ini file (link ‘Settings’ in my signature), on section [MailScanner] the value SmtpListen must be set to 127.0.0.1:25
This way, if you have more than one SMTP application, configure local host:port number 8)