Notebook pro wont BOOT (Grey screen)

Hi ya.

I connected a external harddrive yesterday and had to shut down the laptop without disconnecting it, now it wont boot past the grey screen with the loading arrows.

Tried c button, and CMD R P Control. nothing happened.
When I press the comd S this message comes up

"Single user boot -- fsck not done
Root device is mounted reased only

If you wish to make modifications to files:
/sbin/fsch-fy
/sbin/mount -uwl

If you wish to boot the system:
EXIT"

I havent a clue what to do. Should I try to remove the battery like apple say. I dont like going near the inside just incase. I am at sea so no option of bringing to store for next 3weeks.

Any help would be very much appreciated. Cheers.

Welcome to the Mac Forums.

Reboot the machine and as soon as you hear the POST chime, hold down the OPTION (alt) key on your MBP. Keep holding it until you see the Apple logo and the spinning circle. When your MacIntosh HD appears and the external hard drive (icons), choose the MacIntosh HD and press enter.

That should get you back into OS X. When you get back in, open System Preferences, Startup Disk, and make sure your MacIntosh HD is the default.

Let us know if that works.

Cheers Chscag for your responce.

I took you advice with OPTION (alt) key, the MacIntosh HD thing came up alright and I clicked on it. But unfortunetly it went back to the same grey page with the loading circle. Do I need to insert a dvd or anything for this.

I tried disconnecting the battery and held the power button but no joy.

The CMD cONTROL P R does nothing on my screen.

If you have any other idea plase send my way. Thanks...

Something's not right. I was thinking your MBP was confused over what the startup drive should be, but now I'm a bit inclined to think that your hard drive may be failing.

Let's try a PRAM - NVRAM reset first to make sure your MBP knows which drive to startup from. See this LINK. If that doesn't work, you're going to need to do some trouble shooting with your original startup DVD.

Yep, could be a dying hard drive.

If you can boot with the install DVD in, run disk utility once it boots and try to repair your hard drive. If you hard drive is fine, it could be a bad SATA cable.

Cheers lads.

I took ye advice and now when I hold the Option CMD P & R Button. It does try to reboot now. (That is something it didnt do before). But it just goes back to the grey screen.
I am still waiting on one of the guys onboard to give me his mac cd see if that helps.

It is going to be the 30th of December when I reach Melbourne and everywhere will be shut I imagine. We only stay 3days before heading to Sydney for 1 day. then back to Singapore for the end of January. So its going to be a very boring trip without a laptop. I miss good old Ireland.

My sisters MacBook Pro had this same problem. But differant cause, hers wouldn't start after she updated. The computer booted in Safe mode fine and she could the computer for the most part. Try holding the SHIFT key after the first chime. This will allow you to access your computer, but you can't use some of its functions. I think sound is one of them. Good luck!
- Kyle (Merry Christmas)