Question [Q] Unable to mount internal storage

So a few weeks ago when I tried to flash CM I received the "Unable to mount internal storage" error. I read around and saw some people saying to just do a factory reset. So I did, and to my demise, nothing happened. Same error. And It was even weirder since my root lasted through the reset. Idk if this is suppost to happen or not. I'm so fed up with TouchWiz as of now that I really need a new ROM. Thanks and if you need any other information about the device please ask!