OSX Yosemite 10.10.3 freeze during installation now won't start up help!

I had the same problem. 10.10.3 install got stuck at less than a minute. I rebooted by holding down the power button. After rebooting it started having the same symptoms (spinner and pointer turning on and off, with screen flashes). I tried recovery from timemachine backup, but it wouldn't see my timemachine backup on the NAS. It could strangely see my wifes timemachine though. I started slightly to panic because when I chose restart from the Recovery screen, it kept hanging as well. So I held the power button again to force a shutdown.

When restarting, the Apple logo didn't even show and I started to panic even more. Rebooted into recovery mode again, still couldn't see my timemachine backup. Chose restart again from the recovery screen and this time after a little waiting it started to reboot and strangely enough, this time it rebooted just fine.

I had to enter my iCloud, Facetime and iMessage passwords though.

So my solution is: just keep trying to start up normally. Eventually it may start to work again.

You're not alone...I had SIGNIFICANT problems getting this update to install on TWO different modern, well-maintained Macs. Man....Apple is starting to scare me these days...

Yosemite 10.10.3 Update Will Not Install

Had a similar problem. After the update my MacBook could no longer see my startup disk (flashing folder icon with question mark). After rebooting in recovery and running disk repair I was able to restart again and the install seemed to continue.

Today however I've experienced 2 freezes and one kernel panic and my WiFi connection is very flaky. My wife's MacBook (same specs, same location) has a normal and stable connection, but mine is flaky and very slow. #SNAFU

New Mac Mini 8gB/1tB at 10.10.2 running well after upgrade from Mavericks.

Wife allowed install of 10.10.3 which hung with the infamous "1 second remaining". Left it and went out. Powered it off on return.

Booted, it hung with the bar about 1/3 across. Flickers of the cursor in the upper left hand corner of the screen.

So we booted from last night's SuperDuper backup and backed it up to the Mini's drive.

Now we're back at 10.10.2 and will wait a while to see if Apple sorts this one out.

Try running the combo update.

10.10.3 Combo Update

Type Command-L, which will display the installer log. The installation is moving files. Although it may take a long time, if you can see the progress in the log, it gives some comfort compared to a static progress bar.

This suggestion helped me to install OSX Yosemite 10.10.3 and restart my macbook pro late 2011.

Also, while safe booting ,I have uninstalled few application like adobe cc [which saved me more than 8 GB] then I have removed few data from my Macintosh HD.Then I verified the disk through disk utility.It shown one > SUCCESSFUL with an Error[-Disk couldn't mount the Disk].But completed the steps and I could restart and press CMD+R to repair the Macintosh HD .It was successful and restarted the mac.Hope everything will work smoothly than before :]

I installed the 10.10.3 combo update on a Mac Mini today, now it says "less than 1 Minute" for about 7 hours. What's the best option, should I wait a few hours more, or should I use the power switch to kill the installation?

Is it save to use the repair instruction from this thread in that case, or is it better to go back to 10.10.2 with a time machine backup and to wait until Apple releases 10.10.4 which might not have this bug?

System is frozen with the bar about 40% across. The Command-L doesn't do anything.

Thanks, I really had to use the power switch and then it didn't start anymore. But I was able to boot it in safe mode, installed the remaining updates and used the disk-utitilty to check HD. Last step haven't found any errors, so I could skip the last step (Disk Utility started from Recovery Mode). Up to now everything seems stable! Thanks again for this thread and the solution 🙂

I had the same problem upgrading from 10.10.2 to 10.10.3. My system would freeze during the installation half way through every time and the aforementioned solution above didn't work for me. I tried booting up with the "D" key, the "Shift" key and even tried to boot up with the "C" key with the Mac OS X boot up disc in the drive. None of these worked for me. I then called Apple Support and a sr. adviser suggested I unplug everything from the Mac Pro except the mouse, keyboard and monitor cable. He had me boot up with the Command + R buttons held down after hitting the power button on. This boots up in Recovery mode in which you will see the Disk Utility and a couple other options. He had me run the Disk Utility "verify disk" on the boot up disk. After that proved successful, he had me run the Mac OS X install which installed a fresh copy of OS X. This worked perfectly.