When I try to send test email(all templates except Plain Text) I see this error in the log:
ERROR Exception: System.Net.WebException
Message: The connection to the remote server can not be established.
Source: System
at System.Net.HttpWebRequest.GetResponse ()
at Sitecore.Modules.EmailCampaign.Core.WebContent.DownloadString (String url, Boolean useIisCredentials, String user agent)
nested exception
Exception: System.Net.Sockets.SocketException
Message: It could not be established because the target machine actively refused
When I test it with Plain Text message all works fine.
On the ecm.requestbody page I see this exception:
exception: The connection to the remote server can not be established.
at System.Net.HttpWebRequest.GetResponse ()
at ASP.sitecore_admin_ecm_requestbody_aspx.DownloadString (String url, Boolean useIisCredentials, String iisUser, String iisPass)
Fields IIS.User and IIS.Password in the file Sitecore.EmailExperience.Core.config is also filled
It was a stupid issue with wrong hostname in my hosts(system32/driver/etc/hosts) file