LinuxQuestions.org - [SOLVED] how to send mail in sled system by "mail"

Well lets start this conversation off with 3 simple questions.

1) Do you have a Static IP Address or DCHP IP Address from your ISP?

2) Do you have a rPTR for your IP Address pointing to your Domain Name?

3) Do you have SMTP Authentication turned on?

Now before you answer any of these questions, I am also going to point out that it is best to post the headers of your returned or "Bounced" emails so that a person can provide you with a better answer or resolutions to your current issue. With that said I now want you to answer the first question that I asked...

1) If you answer DHCP to this question then, it is safe to say that you most likely will not be able to send e-mail to the Major hosting providers and anyone who uses any of the major RBLs.
1) If you answer Static then you can move to question 2

2) If you answer NO to this question or you don't know what a rPTR is then again you are most likely never going to be able to send e-mail to any of the major providers and again anyone who uses any of the major RBLs.
2) If you answer Yes, you do have a rPTR setup on your IP Address that does not have your ISPs name in it, then you will need to provide the Headers of the returned E-mails so that someone can help you

3) I ask this as many service providers are now checking to ensure that the mail server that is connecting to them is not an open relay.
3) If you do have authentication turned on the provide some log files, or the headers of the bounced emails

As the following if very vague:
----------------------------------------
hi there,
i want to send some txt eamil to other, but other people couldn't receive any email. i used following commands.
echo "1111111111" | mail -s "test" aaa@hotmail.com -- -f bbb@hotmail.com
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does not give enough details to what might be causing the problem.

Things you need to include when asking for assistance are, the Linux Distro you are using, the Mail service you are running (i.e. Postfix, dovecot, courier, sendmail, qmail, exim....) also you should provide any log entries that might correspond to the problem you are having. You can usually get the info you need by using tail on the mail server log file.

Again, need more info to help you.....