iMac not waking up from sleep after Yosemite upgrade

It's their standard tactic .... wipe your machine out and try to put the blame on you. Others have done this here and it didn't fix anything. It's no longer frustrating, but depressive. LOL

Yep, that's what I told him. I refuse to be a guinea pig anymore. Their engineers need to start taking a look at all of the data we've been sending them in the data captures.

I know one thing - when OS X 10.11 comes along I will not be installing it. Not until I read these (and other) forums to see what shiny new features have borked existing, underlying funcionality.

Yosemite screwed up my mail which required the editing of a plist file to fix. This was, in fairness fixed rapidly; but should never have happened in the first place especially as Mail is such an prominent part of OS X.

I liken this to a car. You take it in to Apple and they immediately change the colour of it, give it new shiny wheels, a spoiler and go-faster stripes. You're a happy bunny because it's free. It's not until weeks later that you discover you can't turn on the windscreen wipers unless you turn the radio off, turn the a/c on and head-butt the dash. They need to sort out what's under the hood first before adding more bells and whistles.

I / we have done our bit. Now over to Apple .........

I just came across this thread and can add this:

I never had the "startup grey screen" issue until I did a total reinstall of Yosemite 2 weeks ago AND began disconnecting my wifi connection when shutting down. Now it happens EVERY time the Imac goes into sleep mode and I try to wake it up.

I have the magic mouse and never leave a USB device connected. I have never activated Time Machine on this computer.

Came across this at http://fieldguide.gizmodo.com/the-worst-bugs-in-os-x-yosemite-and-how-to-fix-the m-1652690924

Specifically ... If you find OS X Yosemite slow to respond when waking up from sleep, there's a rather bizarre fix posted on Reddit that might clear up the problem for you. Apparently the issue is related to an automatic update that hasn't had chance to completely finish.

Well Apple have released the fifth Beta of 10.10.2 to developers a few days ago. They are asking them to:

"continue focusing on problem areas including Wi-Fi, Mail, VoiceOver, and Bluetooth."

We shall see

This whole thing is really started to taint my opinion of Apple. I sent yet another log to the Apple rep yesterday. In the meantime, I have an appointment at the Apple Store to have my MBP looked at since it is exhibiting one of the other "problem areas." It keeps dropping wi-fi after waking from sleep. I've tried all of the suggestions and nothing works.

Oh, and as far as this issue, my iMac continues to fail to wake and then hard reboot even if the drive is not turned on, but is connected.

Just now updated to 10.2.2 - it's in the App Store as public release. We shall see .......

That didn't take long. Still knackered

It's worse. Ejecting the TB drive and switching it off causes OS X to crash completely. On restarting I get kernel panic error message.

So 10.10.2 has not only not fixed the original TB/BT issue is has made it worse. Brilliant 😠

My iMac hasn't failed to wake from the black screen of sleep, ever though I can hear I think activity, since updating, but it failed just before I updated. I don't expect much. I ready to accept this machine will never work as expected. My Macbook Air appears to be working fine. Oh well ....

I have the same problem. It is apparently a bug in Yosemite. There may be various workarounds but the bottom line is that Apple needs to fix it. I have found that if I press the power button for a half second to wake the iMac it generally responds and wakes up. Say 90% of the time. If I press a key or the track pad it will not wake and needs to be restarted by holding down the power button. GL

I had the same problem and i called Apple support i went through to the 2nd level support and this is what they asked me to do.

goto Library/Preferences/SystemConfiguration/com

delete these 2 files

com.apple.AutoWake.plist and com.apple.PowerManagement.plist

It works for me.

Interesting data. Thank you for posting. I haven't stopped fiddling with this. I reset the System Management Controller. This actually worked for a few days. Then it went back to misbehaving. Then I reset the PRAM. This again brought back correct behavior. I'm going to wait and see how long my happiness lasts. May end up giving your fix a go.

GL

I have this problem as well. However I did not do a Yosemite "upgrade" - I did a fresh clean install.

But I also have a USB3 drive connected through a ThunderBolt adapter. I have disconnected that TB adapter and I will see if it happens again.

I am on 10.10.2 on a Mac (27-inch, Mid 2011)