Network is unreachable email error

[hce <webmail.hce@gmail.com>]

Hi,

I am using mutt in Debian, it was workng fine in both receive and send
emails (gmail server), but it is now only working receive email, does
not work to send email since last week, please see following error
message. Any suggestion what I could do wrong?

Dec  9 14:13:48 debian postfix/smtp[13065]: connect to
gmail-smtp-in.l.google.com[209.85.147.27]: Network is unreachable
(port 25)
Dec  9 14:13:48 debian postfix/smtp[13065]: connect to
gmail-smtp-in.l.google.com[209.85.147.114]: Network is unreachable
(port 25)
Dec  9 14:13:49 debian postfix/smtp[13065]: connect to
alt2.gmail-smtp-in.l.google.com[66.249.91.27]: Network is unreachable
(port 25)
Dec  9 14:13:49 debian postfix/smtp[13065]: connect to
alt1.gmail-smtp-in.l.google.com[64.233.179.27]: Network is unreachable
(port 25)
Dec  9 14:13:49 debian postfix/smtp[13065]: connect to
gsmtp183.google.com[64.233.183.27]: Network is unreachable (port 25)
Dec  9 14:13:49 debian postfix/smtp[13065]: 5523B42A9C:
to=<jupiter.hce@gmail.com>, relay=none, delay=2, delays=0.03/0/2/0,
dsn=4.4.1, status=deferred (connect to
gsmtp183.google.com[64.233.183.27]: Network is unreachable)
Dec  9 14:13:49 debian postfix/smtp[13065]: 5523B42A9C:
to=<webmail.hce@gmail.com>, relay=none, delay=2, delays=0.03/0/2/0,
dsn=4.4.1, status=deferred (connect to
gsmtp183.google.com[64.233.183.27]: Network is unreachable)


Thank you.

Jim