Configure SMTP E-Mail in IIS 7 | Microsoft Docs
docs.microsoft.com › en-us › iisMay 14, 2020 · SMTP=localhost sendmail_from = string smtp_port=25 Note that the default value is localhost, so there is no need to change this if SMTP is installed locally. Save and close the Php.ini file. Enable Relay for localhost: Open the Internet Information Services (IIS) 6.0 Manager. Right-click on Default SMTP Virtual Server.