How long does it take to install yosemite? Apple logo is up and the installation bar stopped half way. Been like this for 1hour now! HELP!!!

I'm having the same issue upgrading to Yosemite (13" Retina MBP, late-2013, 2.6 GHz i5, 8GB, 512SSD). Download went fine, and install appeared to start correctly, but after several reboots, the installer is still stuck with the progress slider about 1/3 through. No change overnight. I just restored to Mavericks 10.9.5 from Time Machine. Two partitions, OS X and a Windows 8.1 under Boot Camp. Over 175GB free on the OS X partition, so no storage issues. Please fix!

Should add that Single User works, Safe Boot does not.

I disabled all startup apps and that solved my problem and the computer finally booted. Yay!

My progress bar started out with an estimate of 23 minutes and it actually took about an hour and a quarter. I just waited. In the beginning for about 10 minutes nothing showed on the bar at all. So, just be patient and wait, I would say.

How did you disable all the startup apps (did you do the control+R thing- is there a spot we can try this from when we press the control+R (it might be command+R))

As for the single user- I don't understand what this means- what is single user in comparison to recovery mode?

Mines been going for 8 hours now... I don't think mine is going to move forward any more... I really don't know what to do.

1. I used the power button to shutdown the computer. 2. Then I held the shift key when I restarted to start in safe mode. At first I thought it was going to hang again but after a few minutes it booted. 3. The I went to the users and groups system pref and disabled all startup items. 4. After that I rebooted and it worked.

Very painful process, all installed but will not start properly, keeps freezing at a certain start up point. Come on Apple. Sort this poor customer experience out.

Maybe a weird question but I am not an expert. What happens if I go into safe boot and install the full OSX installer (instead of the update, which I did and gives me all these problems)? Would that work?

If you mean Recovery (Command-R at boot) then reinstall, no this does not help with the post-upgrade hang at the grey screen with progress bar half way across.

Thank-you for the info- if it hasn't fixed itself by the time I get home tonight I'll give that a try. It would make sense in some ways that something could be preventing it from being able to boot. Mine makes it through the whole downloading thing, its just (what I think is) that last screen with the apple and the bar underneath it (with no countdown or anything)

Verbose and Safe:

Darwin System Bootstrapper 2.0.0: Tue Sep 9 16:30:56 PDT 2014; root:libxpc_executables-559.1.22~6/launchd/RELEASE_X86_64

boot-args = -x -v

Fri Oct 17 15:54:16 2014 com.apple.xpc.launchd[1] <Notice>: Safe boot.

** /dev/rdisk0s2

** Root file system

Executing fsck_hfs (version hfs-285).

** Checking Journaled HFS Plus volume.

The volume name is Macintosh HD

** Checking extents overflow file.

** Checking catalog file.

** Checking multi-linked files.

** Checking catalog hierarchy.

** Checking extended attributes file.

** Checking volume bitmap.

** Checking volume information.

** The volume Macintosh HD appears to be OK.

Warning: couldn't block sleep during cache update

Warning: proceeding w/o DiskArb

rebuilding //System/Library/Caches/com.apple.kext.caches/Startup/kernelcache

kext file:///System/Library/Extensions/JMicronATA.kext/ is in hash exception list, allowing to load

Child process usr/sbin/kextcache[8] exited due to signal 11.

Error 107 rebuilding /System/Library/Caches/com.apple.kext.caches/Startup/kernelcache

Safe boot mode detected; rebuilding caches.

/dev/disk0s2 on / (hfs, local, journaled)

BootCacheControl: Unable to open /var/db/BootCache.playlist: 2 No such file or directory

bash: /etc/rc.server: No such file or directory

bash: /etc/rc.installer_cleanup: No such file or directory

ucode: no updates in safe mode

Then it just sits there 😟

No I am going into safe boot (shift key when booting), then log in, go to App Store, look for Yosemite, click on download. The system than says that I already have the update, but gives me the option to download the full installer. I am thinking this should be possible, but there might be things I overlook?

Takes about two hours to completely download and then you may have problems with your WiFi connection. If you have not started, I would wait a few days.

have the same problem installing Yosemite to my mid2010 MBP. Progress bar under apple logo gets stuck midway. Had to reinstall Mavericks.