Macbook stuck at half progressions when tried to boot as Recovery or OS X Utility
I used to installed Windows 7 via bootcamp but removed it recently.
Now, I need to reinstall OS X Yosemite again since i'm letting go my mac.
I have formatted it before for 2 times using the OS X Utility by holding cmd + r when restarting.
It worked perfectly that time.
But it seems like something went wrong when I tried using the same method again now.
I hold pressed cmd + r exactly after the chime but it will stuck at half progression every time.
I even left it like that for 24 hours and came back with the same result.
Also, Ive tried holding opt button when rebooting and the partitions of macHD and Recovery are there but when i clicked Recovery, same thing happen.
So every time it happens, I will shut down by pressing the power button, and start it in again.
I can log on normally to my computer.
This problem occur only when i tried to use os x utility or recovery only.
Are this because of having windows 7 before?
PLEASE HELP ME!!