New computer save/CC transfer

Hey guys so i need some help. i just got a new computer and tried to transfer all my custom content and my saves from my old computer. I transferred every bit of custom content i had there. I started up my game, though, and opened my save, but it first off, said that there was missing CC, but it didn't list all the game mods i had either. My sims were all black (like they looked like they were made of ashes pretty much) and I have no idea what to do. I am not sure what I did wrong. I put everything in the correct folder (packages in the mods folder and sim3packs in the downloads). I installed all the downloads in the launcher. I have no idea what else I need to be doing.