Hi Merk, I believe campaigns do not actually send out when in sandbox. If it shows sent then that's the test and it worked. What I've done in the past is to set up a small group of internal employees (people I have a relationship with who don't mind me testing with them) and send the campaign to them in production. Then I can ask them to reply, click on a link, etc and use that to build out any searches and see the functionality. You can then inactivate that campaign or just add a new group to it.