I am new to Apple and this is my first OSX update. I am not able to get 10.10.4 installed on my MacBook. It fully downloads and starts to install; but the progress bar only moves to about an eight of an inch and stops. I have rebooted and it keeps doing the same thing. Is there a way to re-download the update to see if the one I have is corrupted. Is there any other way to fix this type issue? Thanks for any help you can provide. After 30 years on Windows, I am really enjoying finally having a Mac; but this has been a bit frustrating.