Help!!! My GoDaddy email is being blocked!

Does anyone out there have GoDaddy email? I have had GoDaddy email for several years. I got it in an attempt to brand myself. I loved it's ease to learn, it's ability to form group with a press of a button, and it's ability to organize my data in files. It was almost like an online transaction manager. Several months ago I started to have clients very angry at me for not responding to there e-mails. My agents started asking my why I was not sending out my weekly Broker Bytes. I was responding to emails and sending the newsletters. This concerned me so I started to investigate. I found that charter, verizon, cox, com cast, yahoo, and hotmail were all blocking my emails. The funny part was it was not bouncing back to me. I also found that if my email was any where in another email, like a forwarded email or part of a group, it too would be blocked. I have hired 2 consultants to solve the problem, and have occupied 40+ hours of GoDaddy tech time and have still not solved the problem. The best that anyone could come up with was my email was on a sever that was on a Sorbs blacklist. No one seamed to know how to get it off that black list. So my question it, has anyone had this problem? If so, what did you do?