Pop mail not gmail. Like I stated before it worked fine since she has had the phone a full year, but now it won't work on 4g 3g etc. Only wifi. My Rezound has comcast as well and I don't have any issues with pop mail.
O.K., that helps me understand a little better. Again, I am not an expert by any stretch, but it sounds like something very basic has changed somewhere. It's strange that the phone would just "quit working" in this regard. At first, I would suspect a password change (changed it on-line on a PC, but not on the phone), but then WifFi shouldn't work either, I suspect.
It sounds like you are able to authenticate across your Comcast connection, but not a third-party connection. As a test, you could hook up to a WiFi connection that's not on Comcast (like an AT&T connection at Starbucks), and see if you get e-mail. If not, then I would again go to the phone's settings for getting the e-mail; if so, I am really baffled.
Or, Comcast changed something on their end since the phone was set up.
You could try deleting the entire e-mail account from the phone and starting from scratch (Mail > Menu > More > Settings > Delete Account). I found this post on Comcast's web page:
Setting up Comcast email on Android Charge - Comcast Help and Support Forums
I have not experienced this on Android, but at a previous job we used to use an outside e-mail provider at work when we first put all our remote workers on laptops, and getting third-party e-mail transport was something of a PITA. So we got used to checking e-mail account and authentication settings first.
Apologies for not having a definitive answer.