Go into game settings and check the graphics settings. After the last update all my settings had been defaulted to low. Once I set them all to high my hair and other stuff was back to normal.
I play on a desktop so also check that laptop mode has not been turned on by default too..

Thank you so much! It did go back to normal although the preview still shows the hair as blue, but megh, that's a minor problem. I do run the game in a laptop, so should I still disable the laptop mode? Thank you again!

So I downloaded some hair for my game and in CAS it looks great, but in game it's streaky and weird. Anyway to fix this? Thanks!

I've noticed that sometimes the creators state not to use "Laptop Mode" in your game settings.

The hairs will render better at higher settings.

Good question..... read the link it does explain it a little bit.
http://help.ea.com/en/article/what-...-4-laptop-mode/

If you have a good laptop that has dedicated graphics card then you may not need laptop mode. I thinks its there for lower end laptops with integrated graphics.
Turn it off and if your game has a hissy fit the just re-enable laptop mode
I'm sure someone with better knowledge may step in here and give you better advice.

I've gone and merged the two threads that recently popped up.

I have installed custom hair into my game and have started to use it, in the CAS screen the hair looks fine as if it's working perfectly but as soon as I go into live mode the hair randomly has blond ugly highlights and in the sims thumbnail the hair is all blue! This isn't my first case of installing CC so I'm pretty sure I installed it right but I was wondering what's wrong? Maybe my graphics settings aren't high enough or something? Please help

Merged your thread with an existing one about the same issue. Please read above messages for info.