"Não é possível enviar a mensagem (Destinatário de e-mail não aceito pelo servidor)"

Ao enviar um e-mail surgiu esta mensagem. O que significa? Como corrigir este erro?

Hello Eleno, are you experiencing this after sending a composed message or perhaps after inviting someone to an event? What mail service are you using with eM Client? Are you using a Gmail account?

The error suggests, one of the emails included in the submitted message is not a valid e-mail address, can you make sure your contact you may have used has the address filled out properly and doesn’t contain any typos? Can you also please switch to the Log tab once the error occurs, copy the content of the log and submit it to us here on the forum?

Thank you,