A friend of my just sent me a note complaining that his ISP (which is mine also) blocked another one of his emails today. He received the following message: It was not spam, of course, but an important message sent to friends, family, and associates. And so, naturally, he was a bit upset, to say the least. Upon examination, I noted he sent the message to 80 recipients. Yes, that is a lot, but then again, they were all legitimate, as was the email. And he is paying for the service. I knew most email providers limit email sizes but when I did some digging, I found out that most ISPs limit the number of recipients, and the number of emails sent from a single address per day too. If you use one of the following ISPs or host site email providers: 1and1 AOL APlus AT&T Yahoo! Bell South Bluehost Cablevision / Optimum Charter Comcast Cox EarthLink Gmail GoDaddy HomeStead HostMonster HostWay Hotmail IPowerWeb LunarPages Lycos RoadRunner RockSpace Verizon Yahoo! ...check out your email limit policy here.