Why sometimes I lost my mail that I sent to CityU address from my home PC which connected to Internet via my ISP?
It is because the email was rejected by the anti-spam filters set up on CityU's
incoming mail gateway due to the outgoing mail server of
your ISP was black-listed
by one of the anti-spamming public database used by us to fight with
spam/junk mail (e.g. SpamCop) at the time the email was sent.
The email system of your ISP usually will sent a "undeliverable"
notification to the message sender (i.e. you) and indicates the
undeliverable reason similar to the following one:
Reason: 5.7.1 Blocked - see http://www.spamcop.net/bl.shtml?123.101.102.103: someone@cityu.edu.hk
However, if the sender address appears in your outgoing mail is your CityU
email address, the "undeliverable" notification will also be rejected
by our mail gateway and thus returned to the mail system of your ISP at the
end. That's why you got your mail lost without receiving any notification
from the email systems.
To avoid getting this problem, you are recommended to send your email from
your home PC with either of the following ways:
1. Using WebMail
The WebMail system delivers email via the internal SMTP servers without
routing through the incoming mail gateway, thus by-passing the anti-spam
filtering set up on the gateway. If you just want to sent a short and
simple email, this is a simply and convenience way.
2. Using Virtual Private Network (VPN)
After connecting your home PC to Internet via your ISP broadband or dial-up
service, you can further establish a connection to the CityU Virtual Private
Network (VPN). After the VPN connection is established, your home PC will be
treated as a PC located in CityU's campus network, and you can then send
email with your email client software such as Eudora or MS Outlook Express
on your home PC directly through the internal SMTP servers, just like you
are sending email from a PC located in the campus. With this way, your
outgoing mail will also by-pass the anti-spam filtering set up on the
incoming mail gateway.
In addition, under VPN connection, you need to change the Outgoing Mail
(SMTP) server setting in your email client software to appropriate CityU
internal SMTP servers as below:
For Staff users, set to smtp.cityu.edu.hk
For Student users, set to stdsmtp.cityu.edu.hk
For Alumni users, set to alsmtp.cityu.edu.hk
Return to Email FAQ page
Maintained and supported by Computing Services Centre
E-mail: cc@cityu.edu.hk
Last modified: Tuesday, 24-Jan-06 09:22:51