ho settato nel file di configurazione di ssmtp


sudo gedit /etc/ssmtp/ssmtp.conf

i parametri corretti
codice:
#
# Config file for sSMTP sendmail
#
# The person who gets all mail for userids < 1000
# Make this empty to disable rewriting.
root= miaemaildigmail

# The place where the mail goes. The actual machine name is required no 
# MX records are consulted. Commonly mailhosts are named mail.domain.com
mailhub=mail

# Where will the mail seem to come from?
#rewriteDomain=

# The full hostname
hostname=gmail.com

# Are users allowed to set their own From: address?
# YES - Allow the user to specify their own From: address
# NO - Use the system generated From: address
#FromLineOverride=YES

#root=
mailhub=smtp.gmail.com:587
#rewriteDomain=
#hostname=
UseSTARTTLS=YES
AuthUser=miaemaildigmail
AuthPass= miapasswordinchiaro
FromLineOverride=YES

Il sistema quindi riesce a capire che l'email dell'utente root è miaemaildigmail@gmail.com
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