Installation stuck at grey boot screen on Macbook Pro 4,1 (Early 2008)

I would appreciate any help you guys can give me since I would really like to upgrade my laptop to Mountain Lion.

Computer: Macbook Pro 17" 4,1 (Early 2008) RAM: 4 GB RAM Hard drive: 128 SSD Hard drive Video card: NVIDIA GeForce 8600M GT Current OS: Snow Leopard 10.6.8

Steps I have taken but failed to properly install the OS.

  • Dowloaded Mountain Lion at least 3 times from the App store to make sure the download wasn't corrupted.
  • I even tried making a Lion Bootdisk so I can install Mountain Lion on a USB drive (Install ESD.dmg).
  • I have even tried installing Lion first thinking I would take it one version at a time but gets stuck on boot screen too.
  • I even changed my hard drive to a new blank SSD drive to see any difference.
  • Each time I install Mountain Lion or Lion, everything is good until the installer has to restart the laptop.
  • Laptop gets stuck at the grey boot screen with the Apple logo and the loading circle. Nothing ever happens after.
  • Even waited for 7 hours but no changes in the boot screen.
  • I always had to use/boot to the Snow Leopard CD so I can restart the laptop back to the Snow Leopard drive.

Safeboot gives me this endless message "ERROR: Firewire (OHCI) TI ID 8025 built-in: handleUnrecoverableErrorInt" but I don't have any Firewire cable connected at all.

What can I do next?


I'd do a quick triage to boot the Mac into single user mode to see if the boot drive / base OS is minimally functional. After that, I'd start with systematically working through the startup troubleshooting guide from Apple.

  • OS X: Gray screen appears during startup - http://support.apple.com/kb/TS2570

You've clearly done many of the steps, but the order of steps is very helpful in knowing what the likely cause of the problem is. I might skip removing the SSD if you don't have a HDD - but installing a clean OS onto an external HD at that point might be a good way to rule in or out your SSD as contributing to the failure to install and boot properly.


I had the same exact problem on a MacBook 13″, early 2008.

After many hours, I've come to the conclusion that my FireWire port/controller is the culprit. It's damaged and it doesn't let me install Lion (and I've had problems installing CentOS 64 bits - no problems on the 32 bits version, so 64 bits architecture might be an issue too).

To properly boot Snow Leopard (without waiting 5 minutes to boot…), I even have to remove the FireWire extensions. After that, everything works fine (except the FireWire, of course).

So, I think you might have the same problem: a faulty FireWire port / controller.


I'm reloading the OS on a MacBookPro3,1, and was having the same issue. I inserted a cable into the FireWire 400 port and wiggled the cable (gently) and the problem went away, so it seems like it was just some junk built up on the connector...