Hi everyone

I am having troubles

I have a mac that when you start up freezes on the user login. At one point I was able to log in and the OS/Finder bar kept flashing. At first it was that question mark thing so I reinstalled the os and now it does what I just mentioned

Could this be because of corrupt user system preferences

I have been knocking my head at this for 2 days now

any help is appreciated

cheers