SmarterMail 16.x cannot be connected to Plesk: The server is not responding or cannot be reached

Symptoms

• Local SmarterMail 16.x cannot be connected to Plesk at Tools&Settings > Server Components > SmarterMail 16.x: Plesk loading for 10-15 minutes, but SmarterMail does not appear in list of available Mail servers at Tools&Settings > Mail Server Settings > install and use another mail server;
• SmarterMail web interface is not available with:
  

  CONFIG_TEXT: The server is not responding or cannot be reached. Please try again later. If the problem continues, please check your internet connection or contact your system administrator for assistance.

•  "SmarterMail Service" is running at Server Manager > Tools > Services;

Cause

SmarterMail misconfiguration.

Resolution

1. Connect to the server via RDP;
2. Launch SmarterMail configuration manager at C:\Path_to_smarter_tools\SmarterTools\SmarterMail\IIS Tool\IisConfigurationTool.exe;
3. Follow instructions and select "SmarterMail" website instead of offered one.