cannot send mals using mail command

[neo_in_matrix]

I typed:
$ mail my@abc.com
at shell prompt then entered subject and body message (CTRL+D to end).

mail did not report any errors and I did not get fallback emails. But my@abc.com did not get the email.

What is the possible cause?

Thanks.

[genesus]

A few things to check...

1) It's not in your spam/bulk folder is it?
2) Are the proper ports open on your server?
3) If you are using a router are the proper ports opened/forwarded to allow outgoing mail messages?

4) which mailserver are you using and how was it configured? sendmail/exim4/etc.?

This is not such a hard problem to fix, but it could be many things.