My aunt has Comcast. Two weeks ago they deactivated her email saying that they detected fraudulent activity coming from it. She's been trying daily to get it resolved, including running multiple types of anti-virus and anti-malware programs that they've directed her to use. They refuse to tell her what activity they detected, and no matter how many scans have come back clean, they refuse to reinstate her email access. She otherwise has full internet access for websurfing and streaming. Most of the time, her calls magically get disconnected during the discussion. I have no idea what the real story is there, but having tried to help her fix it, I can attest that they either have really crappy phone service or intentionally cut off her calls as she tries to resolve her issue.
I told her to leave for Google Fiber or Verizon FIOS, but I don't think either has quite reached her doorstep yet.