Recently, I did some research and found other folks who had posted about spam filters with Comcast. We have switched over to Gmail and abandoned our comcast email for this reason. However, as of today, I got an error message noting an IP address that was blocked at Spamhaus.org. It was part of a range of servers that were automatically blocked. Okay, Comcast and Spamhaus, I will give you the fact that spammers send using VPN servers, but a LOT of us are now using VPNs as part of good internet security. So if you block globally, your services are going to be used less or not at all by those of us using good security protocols. Hope this post helps others.