MacBook Pro does not boot past apple screen after replacing hard drive

Question

After replacing hard drive on MacBook Pro 13 inch early 2011 model, the screen only boots to the apple logo.  Do I need to re-install the OS?

Answer 1

The problem is that the OS is not in any where else of the MacBook Pro than in the HD / SSD. If you replace the Hard Drive, then you will need to Re-install OSX into that hard drive, it's pretty easy.
1) Power up your Macbook Pro, as fast as you can press and hold the Option key (ALT). You'll see that it opens the bootable-devices you have, you'll see a Recovery partition, click it.
(If the Hard Drive contains data do the following)
2) In the menu select Disk Utility.
3) In Disk Utility go ahead and select the Hard Drive that is inside the MBP.
4) Erase the content.
(If the Hard Drive contains no data continue with the following jumping the last 3 steps).
5) Select Re-install OSX.
6) Select the Hard Drive in which you want to install it.
Follow the steps of everything else (it should take approximately 1 hour to do the whole thing).
Hope this helps!
Later.