Send Email functionality does not work if Workflow Process Manager Portal is configured with only TLS 1.2. This includes the Send Test Email button next to SMTP server configuration as well as other portal email sending functions such as automation rules' send email action.
Error [Settings] Unable to send email. Server: xxx.xxx.xxx.xxx:25 Client: IP=xxx HostName=xxx Browser=xxx System.Security.Authentication.AuthenticationException: A call to SSPI failed, see inner exception. ---> System.ComponentModel.Win32Exception: The client and server cannot communicate, because they do not possess a common algorithm --- End of inner exception stack trace ---
HTTPS with only TLS 1.2 enabled.
This issue has been reported to Symantec Engineering.
Workaround:
Enable Client TLS 1.0.