Error: Unexpected socket close using node-red-node-email

I get "Error: Unexpected socket close" when using the email send node in the node-red-node-email package. I tried different email-adresses (web.de and yahoo.com) with POP3 and IMAP. Node subtitle in Node RED says "sending..." but then cancels with the above error message. Thanks for any help.

I getting the same error "Error: Unexpected socket close"
I'm trying to set up email to myself. I'm using gmail without 2 factor id.

Does anyone have any ideas or solutions?