Could not connect to FTPS server: NotAfter

When attempting to publish to an FTPS server, users may encounter messages like the following:

Could not connect to FTPS server ( : NotAfter: Sat May 30 06:00:00 EDT 2020

This error indicates that the SSL/TLS certificate configured at the target FTPS server has expired. To resolve this issue, configure the FTPS server with a valid SSL/TLS certificate. For IIS web servers, for example, this involves taking the following steps:

  1. Open IIS Manager
  2. Click on the root node of the IIS server
  3. Choose FTP SSL settings in the right pane
  4. Choose and apply the new SSL/TLS certificate to the root node