I've been trying to send some emails to try and generate some leads, but a lot of the time it seems like they get caught in the spam filter. This is frustrating because I modify each email specifically to its recipient. I am not sending that many, and not spamming in any way. So I'm thinking there must be something that is triggering this. I'm using no images, but do include an address to my website in the bottom, could this be the reason? What general things should I be thinking about to not get put in the spam category?