CAV vs. Earthlink Mail Box

Hi all!
About 6 months ago Little Mac advised me that my ISP, (Earthlink) was purposely blocking my access to my mail using their “Mail Box” POP3 mail program along with CAV. ( I would get to 99% downloaded and then it would freeze up eveytime.) I had to delete CAV and use another antivirus program (Avast). I would love to use all COMODO programs, and do, except for the antivirus. I was just wondering if someone has checked this out lately or if the problem even exists.