Will not boot into Safe Mode

Explain your procedure to boot into Safe mode.

Boot to the Lion Recovery Disk (command-r) and run Repair Disk from Disk Utility.

I am also unable to successfully complete a safe boot:

Boot while holding shift key. Boot progress bar reaches about 25% and then hangs.

To see what was going on, I set nvram boot-args to safe boot + verbose mode:

in Terminal:

sudo nvram boot-args="-x -v"

Rebooted and I see from the verbose display that the hang is when the boot process gets to

** Checking extended attributes file

However, booting from the EFI disk and running Disk Utility, and repairing the disk, it the disk repair does not hang at that step. The disk repair finished correctly.

Nevertheless, safe boot still hangs at that step.

For future readers: To reverse the nvram setting and bypass the hanging safe boot, I boot into single user mode and undo the nvram boot-args setting:

[in single user mode] sudo nvram boot-args=""

Then reboot from single user mode.

korm wrote:

booting from the EFI disk and running Disk Utility

Would you care to elaborate on that?

rob7997 wrote:

I shut down my MacBook. Power it back up being sure to press and hold shift key until gear and progress bar appears, and then release shift key.

For safe boot press the shift key immediately after you hear the boot chime.

fane_j: I have to assume he is referring to the installer dvd but I am not sure why he refers to it as "EFI disk" though.

X423424X wrote:

fane_j: I have to assume he is referring to the installer dvd but I am not sure why he refers to it as "EFI disk" though.

I have no idea what korm means by "EFI disk". However, according to TN2166, the first partition on a Mac-formatted GPT disk > 2GB is the EFI System Partition (aka EFI partition). I do not see how it could be possible to install a bootable copy of Mac OS X on the EFI partition, let alone boot from it and run Disk Utility from it. But there are many things I do not see, hence my asking for an elaboration. I could speculate that he meant the Lion Recovery HD -- but let's wait for his explanation.

I agree.

Reference: 152162960

If you combine verbose safe mode with single user mode, then manually run fsck_hfs before exit, you may more accurately identify the point at which things cease to progress.

Whilst fsck_hfs runs, occasionally key:

Control-T

Note that Control-T does not have the same effect during fsck_hfs when safe mode is without single user mode.

You seem to know more about safe booting than anyone else. Let me tell you my problem and see if you can help at all. Since running parallels for windows was not working well, a techie told me to use boot camp. When I tried to install that, it refused and would not boot up, saying there was no boot drive. I finally had to take my desk top in and they were able to reboot it easily and prepared a short cut for installing boot camp. I did all that and it says it cannot install windows to that partition because its not NTFS or whatever. When I try to restart compputer I am back to black screen that says no bootable drive. I have tried all the short cut keys like shift and C, to no avail. Then it occured to me that since I use a wireless keyboard, the computer might not get far enough to even see the key board. I then tried plugging in a Dell keyboard I had here and still nothing. Can you think of anything I can do short of another trip with a heavy cpu? This is my office computer and I need it badly. Brian

For the Boot Camp question: Boot Camp.

This topic is very specific – OS X that does start and work, but not in safe mode.

If you can not start OS X: Mac OS & System Software.

Good luck!

I am having this problem as well that is persisting with my recent Mountain Lion upgrade. Was there a solution found for this?