Hey guys, I bought my first apple product ever just a month ago: a 2014 macbook pro retina. It worked so far, but I can't update to Yosemite. First try: Time Machine and Filevault enabled, Setup started from Appstore. Result: After several "normal looking" reboots, I was greeted with a black screen and a white, striked-through circle. A clean Yosemite installation and data migration via OSX had the same effect: upon logging in, I saw a loading bar and then only a black screen with the before-mentioned circle. I then contacted apple support and got help from a senior support guy. We finally managed to get the device running again via booting up with cmd + alt + r, installing Mavericks and migrating my data (which took ages). Second try: Time Machine enabled, but no Filevault. Mavericks was obviously a clean install. Setup started again from Appstore. Result: Same as before. After the Setup completed, the device rebooted, I had a black screen, white apple logo and a loading bar. The Apple logo turned into the circle again at ~30% of the loading bar, which vanished. I am completely at a loss now. Should I just go back to Mavericks and wait a bit with the Yosemite update? Could my device broken hardware-wise?