Grey screen on restart after Yosemite upgrade !

Just removing McAfee (whilst in SAFE mode) worked for me.

Phew! This was driving me mad.

Hope McAfee sort this out as I am happier with it but not sure how they will let us all know

Seen lots of Grey Screens and spinning beach balls after Yosemite upgrade on MBA and MBP.

This is sequence worked for me on both Macs:

1. Boot in Safe Mode - this takes time so have a cup of coffee or take the dog for a walk.

2. Turn Wifi Off - I cabled Macs into router.

3. Reboot in Normal Mode - this takes time so have another cup of coffee or take the neighbour's dog for a walk.

4. After successful startup, remove network cable and turn Wifi On.

Also, when the MBA is awoken, I get the spinning ball. So, set sleep time to Never and disable Wifi before closing lid. After opening lid, usual sign in, enable Wifi and off you go. I think that Apple should be addressing these issues as they are not uncommon with 10.10.

It works for me.

THANK YOU. Was driving me crazy and had to wait over a week for appt. at apple. Removed mcafee and all works perfectly.

OK - McAfee do know about the problem - see page below

https://kc.mcafee.com/corporate/index?page=content&id=KB83053

You must upgrade McAfee Agent (MA) for Mac to MA 4.8 Hotfix 972377 and MNE 2.0 to MNE 2.0 Patch 1 (2.0.1) before upgrading the operating system to Yosemite.

Alternatively

For systems that have already upgraded to Mac OS X 10.10, perform the following steps:
1/ Download the MNE 2.0.1 standalone installer package.

2/ Run the MNE 2.0.1 standalone installer package on each Mac client system. This applies the required MA 4.8 Patch 2 Hotfix 972377 and upgrade MNE 2.0 to MNE 2.0.1

I have not the faintest idea how to do this as I get my McFee as part of BT Infinity package I don't have a direct account with McFee.

Suggestions welcomed

For those of you with BT Infinity who have your McAfee as your NetProtect Plus facility.

I contacted BT Broadband and the guy there (Hussain) contacted the NetProtect Team who said they were aware of the incompatability problem they have currently with Macs running Yosemite.

A compatible version of McAfee would be available 'soon' but no date given or how you would find out if it was the updated version without having to install it and 'suck it and see'.

Another BT NetProtect help guy (Krish) said that you don't need virus protection on a Mac anyway as Apple's virus protection is very strong anyway.

Guess I will give it a week (or two) and try it again.

I have followed the instructions above and agree - if you give it time then ultimately it runs...

The problem is that this can be hours from restart, to login, to menu bar, to dock, to application launch. I eventually got it running and did a console display - no errors.. Just running VERY slow. 20+ minutes to lunch anything.

So I restarted in Recover Mode (Command-R) while still connected to the wired network and did a Reinstall OS X. This has worked perfectly...

I used the wired network as it would seem that the client needs to authenticate you against the App Store and this will not work over wireless on my works WPA/WPA2 Enterprise authentication.

I got the grey screen after ttying to install the Yosemite upgrade on my Mac Pro. Could not access the CPU in any way. Tried the power button. No chime, no key holds on the keyboard worked. No hard drive activity whatsoever. Tried removing all 4 drives and replacing boot drive with another which had Leopard. Still no signs of life. Tried popping the SuperDrive and manually opening the tray to see if I could boot from an older OSX install DVD. Nothing. Just the grey screen.

Here's the only thing that worked: plugged keyboard into USB port on CPU (it had been in my 30" Cinema), hit power button, zapped PRAM, command option P-R, held thru THREE chimes. Then I finally got the Apple logo and progress bar. Yosemite finished installing and seems to be working now. This was a HUGE scare, I thought I lost everything.

Whew! 2 1/2 days of Grey Screen.

Restarted once and it came up partially completed, started running the upgrade and retired back into the grey screen.

Then I waited until this morning. Mouse, screen, keyboard show no signs of life.

Prepared to hit power button to reboot and hit shift to load in safe mode when... my face and login popped up center screen.

So I logged in.

At this point it asked "continue installation?" and I clicked yes.

It showed me a 7 minute timer and 7 minutes later ICLoud Update, and a few minutes after that - I had Yosemite.

Lesson learned: trust Apple. Oh, and back use the backup tools next time.

Thanks for all the advice and feedback.

Hope this helps some of the novices like me.

Annie

Here is what I did and it seems to be working:

1. Turned CPU on in Safe Mode by Holding down Shift: Initially, the grey screen and download bar appeared and after going to about 50% both disappeared and slowly a login came up.

2. Logged In: This took some time as it took the computer some time to register that i selected this option.

3. Continue Download: After logging continuation of the download appeared with about 7min to go.

4. Home Screen: in the most painful way imaginame, pixel by pixel, the main page emerged. The upgrade was obvious and the performance was extremely slow. Even moving the mouse pixilated the screen.

5. App Store Update: I checked to see if there was any additional OS X updates and there was. I clicked to download & restart.

6. Start of Download & Restart: computer began its downloading and Grey Screen Again... lol...But hope was not lost.... Just when it seemed that all failed...

7. Re-re-restart...: Restarted the computer again in safe mode, logged in -this time there was no additional downloading of any kind- and once on the main screen, I Turned Wi-Fi Off. Then, you guessed it... Re-started the computer

8. Finally, it restarted without any loading going on and took me straight to Log In. Logged in, everything looks good so far!

PS: I also turned File Vault Off, however i doubt this has any effect.

Hope this helps

i had this problem and restarted and shut down about 50 times. It is likely due to start up items that need to be removed/launch items in one or two of the library folders. Chat to the apple team via chat message and they can take you through the right steps to stop this and get your mac back to full use :-)

I had the same issue. This worked for me:

I restarted in safe mode by holding shift at startup.

Opened the App Store.

Then, I updated everything that appeared as available Updates.

Then, I restarted.

FIxed.

My husband just had this exact same problem, so we followed the instructions about booting up in Safe Mode, (thanks, everyone, for the advice, and also for including that Safe Mode can take a long time to start!) and found that he actually didn't have McAfee installed, but did have another anti-virus software (Sophos) instead. Here's all we did:

• Restarted the Mac and opened in Safe Mode. (And waited waited waited for it to compute that we were trying to open in Safe Mode.)
• Uninstalled Sophos.
• Turned off the Wi-Fi, just as an added precaution.
• Restart.

The progress screen still showed up, but finished downloading within minutes! So far, seems to be fixed.

Unless Sophos and McAfee are sister companies, or something, (we're not computers whizzes over here, so we wouldn't know) it seems that some anti-virus applications are incompatible with Yosemite. Bottom line, if anyone else has an anti-virus application that is not McAfee, like us, then it's still worth a try to uninstall your anti-virus software and see if that fixes the problem.

Hope that helps someone else!

TimUK,

I have the exact same symptoms as you. Can't boot into Safe Mode no matter how long I wait holding the shift key. Don't have McAffee. Flashing PRAM takes me to the 50% progress screen, where it hangs. Time to make a service appointment with the genius boys.

Just had the same problem today

i got the grey screen after restart. i tried a few times, same result.

I'm no expert at all. So I did the Hold C reboot /Disc /Utilities/Verify disc/ a load of Library errors came up.i clicked repair..it ran though the sequence.said fixed. I rebooted the same..grey screen

i put laptop on and came here..

Followed the open in safe mode suggestion.it did and came up with Completing Installation 2min..if finished I rebooted and all fine..Maybe this was all that was needed. the Safe mode finish installation..

I'm going ot be wary of doing more Yosamite updates This never happened with Maverick,wish I could go back..

For those of you with BT Infinity who have your McAfee as your NetProtect Plus facility.

You might want to have a read here:

http://www.thesafemac.com/tag/anti-virus/

Personally, I have no AV software installed; instead, I try to practice safe computing.