Since AcyMailing 3.7.0, we included in all our paid versions a spam test so you can easily test your Newsletter against spam filters (SpamAssassin), check your server configuration and malformed content.
When you preview a newsletter, you will see a button named "Spam Test" in the top right corner of the window. Click it to start the test.
AcyMailing will send an e-mail from your server and check it.
If this is the first time you run a test for this newsletter, you will be asked to wait a few seconds in order for your mail to be processed.
Once your newsletter is processed, you should be able to see the following page with your score.
When you scroll down you get a detailed result. And if you want to know more about it click on a test title.