SMTP Error, Could not connect to host with Amazon

Hi there

Trying to set up the eNewsletter plugin on my site and have authenticated the from email on Amazon SES account.

When I set up all details in plugin...

smtp username
smtp password

both generated in the SES amazon portal and used in the plugin settings.

Then hit the test, I get this error message
SMTP Error, could not connect to host

Checked and re-entered details again and set port to 25 etc, but just not working for me.

Hope you can help,

Many thanks