Mail is not working.

# mail andrew_kennedy7@yahoo.com
Subject: test
testing
EOT
# /usr/sbin/sendmail: No such file or directory
"/root/dead.letter" 9/223
. . . message not sent.

You might have to setup 'mail' software with msmtp and use a smtp server of your email provider (recommended).

Read msmtp man page it has good examples of setting it up.

Or you can use one of postfix, exim, opensmtpd., the original sendmail(asked by your mail program).

Using these depending on your ip address may have problem in reaching the targets(blacklisting of ip addresses very much prevalent based ISP).

So the error clearly tells you that you don't have a sendmail program...did you install it? Did you configure a mail system (postfix/sendmail)? What kind of environment are you using (home or corporate?), and do you have a relay further upstream to use? Or are you wanting to use Yahoo or Gmail SMTP relays to send mail??? You provide next to no details about things, including version/distro of Linux, anything you've done/tried so far, or if this a new problem and it was working, or you've just now tried it. We need details before we can try to help you.
This is misleading and partially incorrect, along with being hard to read/understand. An ISP MAY blacklist people from SMTP servers, and it MAY be based on IP address...but if the user hasn't sent any emails, the only way this would be true is if the OP got their IP address from a former spammer who WAS blacklisted. Chances are, the ISP will allow SMTP access, and has instructions on how to set it up.

Also, the email recipients won't have ANY problems receiving that email, unless (as stated), the OP is sending from either an IP or address that was ALREADY blacklisted. The targets should receive anything just fine otherwise.

I was not posting of sender's ISP at all. Many email providers gmail, yahoo, hotmail and etc usually blacklist email send directly from one of ISP's provided dynamic ip address connections. They do this as many internet users of ISP's regularly send spam messages. But if you purchase clean Ip address from ISP's then it may not be in blacklist.

Sorry, that's wrong. They do NOT blacklist ANYONE without a reason, because if they did, they'd take millions of small businesses offline with such a blanket policy. And the OP never said they had a dynamic address (or ANYTHING about their ISP or address), did they??
Sorry, that's wrong too. Many internet users send spam mail PERIOD, and many don't even know they're doing it, thanks to botnet infected PC's. And how, exactly, do you 'purchase' a clean IP address? How would ANYONE know it's 'clean'?

99% of ISP's have documentation on how to configure mail services to work with their connections....they wouldn't do this if everyone who set one up was automatically blacklisted, since that would be a total waste of everyones time.

Tbone,

My sig shows my Linux version.

After seeing how much work is involved in getting sendmail to work, I decided to stick witk seamonkey 4 sending emails.

Anyone know if any command line versions of email clients in windows work under wine?

Ok, but lots of folks have different versions noted in their user info/sigs, and you may have been talking about another machine. Always best to say what you're using.
Doing ANYTHING with wine, when there are programs for Linux that do the same thing, is unnecessary. The msmtp or mailx programs can both be used, in conjunction with your existing ISP's mail system, to do exactly what you're after.

If all you want is to send a few emails for yourself, then sendmail/postfix are overkill.

echo "something" | mailx -s "subject" recipient@somewhere.com

yields no email in my inbox.

And no error message either.

Did you configure mailx? Set up the resource file??? Until you configure a program, you can't use it, anymore than you can just run ANY mail program without configuring it.
http://linux.die.net/man/1/mailx

The man page has information on how to use mailx with IMAP/POP3.

Okey dokey.