SMTP on v4 platform using TLS on port 25

Hi All, Our application on V4 of the platform use SMTP via our own server with username/password authentication. We use TLS over port 25. Since a few weeks the application is no longer able to find the SMTP server (connection timeout). Do we need some special permissions when using TLS over port 25 or is this blocked somehow? com.mendix.core.CoreRuntimeException: com.mendix.systemwideinterfaces.MendixRuntimeException: org.apache.commons.mail.EmailException: Sending the email to the following server failed : at EmailTemplate.SendEmailMessage (JavaAction : 'Send Email') at EmailTemplate.IVK_SendTestMessage (SubMicroflow : 'SendEmailMessage') ... Caused by: Couldn't connect to host, port:, 25; timeout 60000 at com.sun.mail.smtp.SMTPTransport.openServer( at com.sun.mail.smtp.SMTPTransport.protocolConnect( Any help appreciated
1 answers

If you read the docs you will find

Please note that sending email from Mendix Cloud v4 cannot happen over port 25. This port is open, but it is heavily rate-limited by the infrasture provider, so you will experience issues. 

regards, Fabian