I have couple of domains where I run a website and I have created email accounts for all of these domains. I did a test and sent an email from each of these email accounts to my Gmail accounts (couple of them), but the emails goes automatically to spam box. One of my buddies told me that the email I sent to him from these domains went to his spambox as well (he doesnt have a gmail account). I asked from the support of my webhosting account and they told me to enable Domain Keys and SPF from the cPanel and so I did, but it didn't help. All of my domains are legit (no spam activity) and has been registered only by me. What could possibly cause this?