I have installed the plugin in test enviroment

I have installed the plugin in test enviroment and everything worked fine. I have installed now in my prodiction site and imported the subscribers, 4000 users.
Initially i configured it to send emails using easy SMTP plugin but it gave errors and then i installed in without SMTP.

I have published my first post and i have not received anything. It suppose to start sending mails inmediately. I have checked the mail quee but nothing is there.

I have put 250 mails per hour so there is no problem. this blog is in my VPS.

In the options of the plugin, in "subscriptions, email sent", there are no emails sent....

How can i know what is happening?