Need Help - Error Submitting the form

[jhe01]

Hello,

I am receiving an error after test of form submit (check image below).

I have latest version of neos/form-builder and already installe Neos.SwiftMailer.

I also set the confirmation message and email finisher of the form

Thank in advance for help!

[Kleisli]

I know, you asked this 2 years ago, but just in case someone else is looking for a solution: I got the same error and couldn't solve it otherwise than switching from using Swift_SendmailTransport to Swift_SmtpTransport using an Email-Account on my mailserver.