For example, , @abc.com is my domain name, receiving email
uses POP3, and sending email uses SMTP, can any unknown sender send any
out-going email under without getting any authority from the
source abc.com? If they can successfully send out email, do they access my
SMTP illegally?
Thanks in advance for any suggestions
Eric

Thank you very much for your suggestions
If anyone can put anybody else's email address in the sender email address
field without authorization required, can they receive anybody else's email
address?

Furthermore, if the domain name for email address uses dynamic IP Address,
which is not allowed to send into any hotmail account based on their policy.
Can anyone put anybody's else email address, which domain name uses a static
IP Address, and send into any hotmail account. Even through anyone is using a
dynamic IP Address, but from the viewpoint of hotmail server, which can see a
static IP Address, and skipping the hotmail policy.
I look forward to your reply
Thank you very much for any suggestions
Eric

"N. Miller" wrote:

On Wed, 7 May 2008 07:28:08 -0700, Eric wrote:

For example, , @abc.com is my domain name, receiving email
uses POP3, and sending email uses SMTP, can any unknown sender send any
out-going email under without getting any authority from the
source abc.com? If they can successfully send out email, do they access my
SMTP illegally?
Thanks in advance for any suggestions

Anybody can put anybody else's email address in the sender email address
field. No authorization required (except in rare cases, where the service
provide requires verification of the sender email address). They normally
can't access any SMTP message submission server without access permissions
granted by the server administrator; unless the server is intentionally
configured as an open relay.

--
Norman
~Shine, bright morning light,
~now in the air the spring is coming.
~Sweet, blowing wind,
~singing down the hills and valleys.

"Eric" wrote in message
...
: Thank you very much for your suggestions
: If anyone can put anybody else's email address in the sender email address
: field without authorization required, can they receive anybody else's
email
: address?

No...not unless they have the appropriate username/password credentials.


:
: Furthermore, if the domain name for email address uses dynamic IP Address,
: which is not allowed to send into any hotmail account based on their
policy.
: Can anyone put anybody's else email address, which domain name uses a
static
: IP Address, and send into any hotmail account. Even through anyone is
using a
: dynamic IP Address, but from the viewpoint of hotmail server, which can
see a
: static IP Address, and skipping the hotmail policy.
: I look forward to your reply
: Thank you very much for any suggestions
: Eric
:
: "N. Miller" wrote:
:
: On Wed, 7 May 2008 07:28:08 -0700, Eric wrote:
:
: For example, , @abc.com is my domain name, receiving
email
: uses POP3, and sending email uses SMTP, can any unknown sender send
any
: out-going email under without getting any authority from
the
: source abc.com? If they can successfully send out email, do they
access my
: SMTP illegally?
: Thanks in advance for any suggestions
:
: Anybody can put anybody else's email address in the sender email address
: field. No authorization required (except in rare cases, where the
service
: provide requires verification of the sender email address). They
normally
: can't access any SMTP message submission server without access
permissions
: granted by the server administrator; unless the server is intentionally
: configured as an open relay.
:
: --
: Norman
: ~Shine, bright morning light,
: ~now in the air the spring is coming.
: ~Sweet, blowing wind,
: ~singing down the hills and valleys.
:

If they operate their own SMTP server they can put anything they want in the
headers OE shows you.

"Eric" wrote in message
...
Thank you very much for your suggestions
If anyone can put anybody else's email address in the sender email address
field without authorization required, can they receive anybody else's
email
address?

Furthermore, if the domain name for email address uses dynamic IP Address,
which is not allowed to send into any hotmail account based on their
policy.
Can anyone put anybody's else email address, which domain name uses a
static
IP Address, and send into any hotmail account. Even through anyone is
using a
dynamic IP Address, but from the viewpoint of hotmail server, which can
see a
static IP Address, and skipping the hotmail policy.
I look forward to your reply

"N. Miller" wrote:

On Wed, 7 May 2008 07:28:08 -0700, Eric wrote:

For example, , @abc.com is my domain name, receiving
email
uses POP3, and sending email uses SMTP, can any unknown sender send any
out-going email under without getting any authority from
the
source abc.com? If they can successfully send out email, do they access
my
SMTP illegally?
Thanks in advance for any suggestions

Anybody can put anybody else's email address in the sender email address
field. No authorization required (except in rare cases, where the service
provide requires verification of the sender email address). They normally
can't access any SMTP message submission server without access
permissions
granted by the server administrator; unless the server is intentionally
configured as an open relay.

There's nothing you can do to prevent anyone from sending an e-mail with
your e-mail address as the From header, just as you can't prevent anyone
from sending a postal mail and putting your name and address as the
return address.

I don't know how much checking Hotmail does.

A receiving mail server can check that the IP address of the sending
server matches the domain name it claims to be.

It could also check that the From header domain matches the domain that
the mail server claims to be. But there are legitimate reasons why they
could differ, as when a sending mail server supports multiple domains.

--

Mike - http://pages.prodigy.net/michael_santovec/techhelp.htm



"Eric" wrote in message
...
Thank you very much for your suggestions
If anyone can put anybody else's email address in the sender email
address
field without authorization required, can they receive anybody else's
email
address?

Furthermore, if the domain name for email address uses dynamic IP
Address,
which is not allowed to send into any hotmail account based on their
policy.
Can anyone put anybody's else email address, which domain name uses a
static
IP Address, and send into any hotmail account. Even through anyone is
using a
dynamic IP Address, but from the viewpoint of hotmail server, which
can see a
static IP Address, and skipping the hotmail policy.
I look forward to your reply
Thank you very much for any suggestions
Eric

"N. Miller" wrote:

On Wed, 7 May 2008 07:28:08 -0700, Eric wrote:

For example, , @abc.com is my domain name, receiving
email
uses POP3, and sending email uses SMTP, can any unknown sender send
any
out-going email under without getting any authority
from the
source abc.com? If they can successfully send out email, do they
access my
SMTP illegally?
Thanks in advance for any suggestions

Anybody can put anybody else's email address in the sender email
address
field. No authorization required (except in rare cases, where the
service
provide requires verification of the sender email address). They
normally
can't access any SMTP message submission server without access
permissions
granted by the server administrator; unless the server is
intentionally
configured as an open relay.

--
Norman
~Shine, bright morning light,
~now in the air the spring is coming.
~Sweet, blowing wind,
~singing down the hills and valleys.

Thank everyone very much for suggestions
Based on my case, sender successfully sends email to receiver for hotmail
account. Therefore, let assume that hotmail does not accept sender using
Dynamic IP Address, at this moment, sender still using Dynamic IP Address for
SMTP, but they change the domain name for email, such as @abc.com, which is
using Static IP Address. Sender can successfully send email, even through
they are using Dynamic IP Address for SMTP, therefore, hotmail only check
for domain name to confirm a Static IP Address. Am I right?
Thank everyone for any suggestions
Eric

"Michael Santovec" wrote:

There's nothing you can do to prevent anyone from sending an e-mail with
your e-mail address as the From header, just as you can't prevent anyone
from sending a postal mail and putting your name and address as the
return address.

I don't know how much checking Hotmail does.

A receiving mail server can check that the IP address of the sending
server matches the domain name it claims to be.

It could also check that the From header domain matches the domain that
the mail server claims to be. But there are legitimate reasons why they
could differ, as when a sending mail server supports multiple domains.

--

Mike - http://pages.prodigy.net/michael_santovec/techhelp.htm



"Eric" wrote in message
...
Thank you very much for your suggestions
If anyone can put anybody else's email address in the sender email
address
field without authorization required, can they receive anybody else's
email
address?

Furthermore, if the domain name for email address uses dynamic IP
Address,
which is not allowed to send into any hotmail account based on their
policy.
Can anyone put anybody's else email address, which domain name uses a
static
IP Address, and send into any hotmail account. Even through anyone is
using a
dynamic IP Address, but from the viewpoint of hotmail server, which
can see a
static IP Address, and skipping the hotmail policy.
I look forward to your reply
Thank you very much for any suggestions
Eric

"N. Miller" wrote:

On Wed, 7 May 2008 07:28:08 -0700, Eric wrote:

For example, , @abc.com is my domain name, receiving
email
uses POP3, and sending email uses SMTP, can any unknown sender send
any
out-going email under without getting any authority
from the
source abc.com? If they can successfully send out email, do they
access my
SMTP illegally?
Thanks in advance for any suggestions

Anybody can put anybody else's email address in the sender email
address
field. No authorization required (except in rare cases, where the
service
provide requires verification of the sender email address). They
normally
can't access any SMTP message submission server without access
permissions
granted by the server administrator; unless the server is
intentionally
configured as an open relay.

--
Norman
~Shine, bright morning light,
~now in the air the spring is coming.
~Sweet, blowing wind,
~singing down the hills and valleys.