Se inviando una mail da una casella del dominio ricevo l’errore: Sorry, no mailbox here by that name. vpopmail (#5.1.1)

Hi. This is the qmail-send program at mxN.aruba.it.
I'm afraid I wasn't able to deliver your message to the following addresses. This is a permanent error; I've given up. Sorry it didn't work out.
 
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nomecasella@nomedominio.xxx>:
Sorry, no mailbox here by that name. vpopmail (#5.1.1)

La casella indicata non esiste. Per crearla occorrerà accedere al Admin Mail, come indicato in “Come creare le caselle di posta del dominio”.