If you are testing your autoresponder after integration, you must use an actual email address that has not been used previously in an email list. This is a rule set by the autoresponder you're integrating with, not by OSP. You may need to check your spam folder or social/promotions tab if using Gmail. Emails are sent via the autoresponder such as AWeber, GetResponse, or others.
The best way to test is to enter your own email address, and then check your spam/junk/promotions folder. Know that this will work only the first time, as the autoresponder will then add your email to the campaign list.