Hi, Since installing Mavericks, every now and again my MBP freezes at start up, sometimes on desktop screeen, sometimes on the password screen (after password entered). When it happens, I hold the power button down to switch off. It generally happens 2 - 3 times in a row, then logs on fine. Happened on 3 seperate occasions now since maverick uploaded (on day 1 of release). Anyone any clues on potential reason? Would rather not restore pre-maverics back up as I've added a lot of data to MBP since then, and dont really want to have to add it all again. Thanks in advance for any help anyone can give.