I have yet to look into this, but no doubt easySMS somehow is sending unsolicited emails as I got the bounces back.
<firstname.lastname@example.org>: 18.104.22.168 does not like recipient. Remote host said: 550 Requested action not taken: mailbox unavailable Giving up on 22.214.171.124. <email@example.com>: 126.96.36.199 does not like recipient. Remote host said: 550 Requested action not taken: mailbox unavailable Giving up on 188.8.131.52. <firstname.lastname@example.org>: 184.108.40.206 does not like recipient. Remote host said: 550 5.1.1 <email@example.com>: Recipient address rejected: User unknown in virtual mailbox table Giving up on 220.127.116.11. <firstname.lastname@example.org>: 18.104.22.168 does not like recipient. Remote host said: 550-5.1.1 The email account that you tried to reach does not exist. Please try 550-5.1.1 double-checking the recipient's email address for typos or 550-5.1.1 unnecessary spaces. Learn more at 550 5.1.1 http://mail.google.com/support/bin/answer.py?answer=6596 b11si2890529ana.182 Giving up on 22.214.171.124.
These bounces were certainly from easySMS as they contained the subject of the last two SMS's I sent.
These addresses have NEVER been associated with my wp install, nor have they ever been entered through the easySMS form. The only possible way my site could have even seen these addresses is possibly spam through my contact form, but I fail to see the connection.
I'm going to dig into the database now and then once over the plugin code and see what I turn up.
Has anyone else experienced this with this plugin?