Ok, so I have experienced my first real bug with Yosemite. I was letting someone use my laptop trying to convince them to upgrade to Yosemite when they clicked on iBooks and it popped up with this error: They told me and I came over and clicked "Don't Reopen". Then I was greeted with the standard "iBooks quit unexpectedly." I reported it to Apple then tried again. Same thing. I opened up the Console and pulled up the crash. This is the top 1/8 of the crash. I can post the whole thing if needed, but I don't think it would be necessary and would probably be more characters then allowed by the forum. Process: iBooks  Path: /Applications/iBooks.app/Contents/MacOS/iBooks Identifier: com.apple.iBooksX Version: 1.1 (582) Build Info: iBooks-582000000000000~9 Code Type: X86-64 (Native) Parent Process: ???  Responsible: iBooks  User ID: 501 Date/Time: 2014-11-04 17:04:33.369 -0800 OS Version: Mac OS X 10.10 (14A389) Report Version: 11 Anonymous UUID: (removed for privacy reasons) Time Awake Since Boot: 210 seconds Crashed Thread: 10 Dispatch queue: com.apple.BKLibrary.reloadQueue Exception Type: EXC_CRASH (SIGABRT) Exception Codes: 0x0000000000000000, 0x0000000000000000 Application Specific Information: dyld: in dlopen() /System/Library/PrivateFrameworks/CoreFP.framework/CoreFP *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid parameter not satisfying: _managedObjectModel' terminating with uncaught exception of type NSException abort() called I rebooted (as you can tell). I tried to Repair Permissions nothing came back for iBooks. Verified Disk, everything OK. SMC+PRAM reset didn't help (didn't think it would), and neither did a new user account. Booted in Safe Mode, same issue. I'm thinking about doing a complete reinstall although I would prefer not to. I was told to do that by AppleCare but that is always their answer to everything. It is worth nothing that I also updated to 10.10.1 B1 and the issue was still occurring. So this isn't just 10.10.1 but also 10.10. Is there anything, anything at all I can try before I reinstall OS X? Any help would be greatly appreciated! Thank you.