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Why Does My Mac Always Try to Boot Off the Wrong Disk?

Upon attempting a Software Update, I was told I didn't have enough memory and was to remove unnecessary items from my Start Up Disk, I seem to have my HD in my Start Up Disk (is that normal?).

I simply restarted my machine to find that there was a flashing square box with a globe in the centre. After about a couple of minuets of this flashing an old OS 9 emblem (two faces) in a folder flashing up along with a question mark.

It now does this all the time. Could you tell what is going on here.

Dave's Answer:

You're not the first to get into this situation, but the good news is that it's surprisingly easy to fix it! The problem is that you've ended up indicating that the wrong drive or partition on your computer is where the "bootable" operating system can be found.

Your Mac then dutifully looks on that disk for an OS it can use, eventually decides it can't find one and stalls out.

To fix it, if you can get your computer to come up (sometimes the computer will automatically search for other disks that have a bootable operating system), then go to Apple --> System Preferences --> Startup Disk. You'll see this:

Choose the disk that does have the version of the operating system you want and choose Restart and your problem should be solved.

Failing that, if you can't get your Mac to startup so that you can get there in the first place, hold down the Option key. You'll then get a list of different operating systems found on your computer: select the correct one and continue startup up your system.

Good luck with this!

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Comments

Thanks for the great tip Dave. Can we take this one step further. Once I get the globe image at startup time, it will them time out to a folder flashing a "?" question mark. From my research that indicates some type of permission problems. I've been told I should fix permissions before and after installing new software. How should this be done ? There is also supposed to be a key squence that you can hold down at boot time to be presented with a unix shell, which will allow you to run FSCK -y to fix any disk issues.

Do you happen to know what this is ? I thought it was option + s , then power on the machine. This does not seem to work when I try it.

Thanks!

Posted by: Steve at November 6, 2005 10:02 PM

Fix permissions by running the program Disk Utility (which can be found in your Applications -> Utilities folder). Select your disk in the app, then choose "Repair Permissions". Easily done.

Posted by: Dave Taylor at November 7, 2005 4:24 PM

Thanks for the help! If, like mine, your computer gets stuck after the dreaded globe icon and you want to fsck, you can press command-s WHILE the computer is starting up (not before), then type "fsck[SPACE]-y".

Posted by: Daniel at February 20, 2007 1:52 PM

i have the flashing globe on start up then after that it's a folder and a question mark that flashes. i've tried everything to get it to boot, when i hold down the option key it brings up a screen with a locked lock and a box where i can type stuff and then an arrow pointing towards the right, help please

Posted by: Taylor at September 8, 2007 6:05 PM

My G4 flash message : System software only works on original media, not if copied to another drive.

I want to clean format the startup disk using OS X with classic .... how can I do that. please help my system seems to be crashed and it stops at this message asking me to Restart. I used Option key (doesn't work)/ Holding C to boot from CD ( not working ).

Thx in advance,

Aziz

Posted by: Aziz at April 12, 2008 2:50 AM

Hey, Dave I was wondering why when I hold down option the disk that I backed up does not show up as one of the choices to start up from?

Posted by: Isaac at December 29, 2008 7:33 PM

I have a lot to say, but ...

I have a lot to say, and questions of my own for that matter, but most of all I'd like to say thank you for all your efforts on this Web site by buying you a chai!

I do have a comment, now that you mention it!