Q: Hi! My mac Lion won't start after 10.7.4 Update.

When you hear the startup tone hold down the Option key, choose the internal HD and it should start. Next open System Preferences - Startup Disk and make sure your internal HD is selected. After it's highlighted then click Restart to test.

I would also recommend opening Disk Utility (Applications - Utilities - Disk Utility) and running Repair Disk Permissions on the internal HD. If you see messages you can ignore them per Disk Utility's Repair Disk Permissions messages that you can safely ignore.

Similar issue here. Wife saw a message on the screen (after update to 10.7.4) to reboot. She rebooted & now the macbook pro is dead -- nothing, nada, zilch. Tried a million things in some of these other threads and can't get anything on the screen.

Hear the system working in behind the scenes, e.g. attempting to boot to the restore CD. Tried an external monitor (yay, more $$$ for apple for a thunderbolt -> dvi module) and can't get anywhere.

Stefambe,

First make sure your data is backed up, or recovered to another hard drive as is outlined on this tip:

https://discussions.apple.com/docs/DOC-1992

Once backed up, repairing permissions certainly may help, but also booting off the recovery partition and repairing the directory with the First Aid - Repair Disk function of the Disk Utility of the Lion installer.  Boot off the recovery partition with the command and R keys.

If the Repair Disk function fails (not the repair permissions), then you may need to purchase Alsoft Disk Warrior. If Disk Warrior fails, then replacing the hard drive may be necessary.

If none of these appear to boot, you may have to remove all third party peripherals before you begin.

Davidandgoliath,

Please start a new topic thread.  While the issues may be similar, you'll get a wider audience, and won't confuse Stefambe with solutions that don't apply to them.

Apple pulled my posts for complaining. I am working on a solution now. Whats your system?

Then stick with 10.7.3 until you are certain all your software and hardware supports 10.7.4.  You obviously have something that is not 10.7.4 compatible.

Currently I have found an recent NVidia update that I did not have prior to my problems.

I am near the end of a clean reinstall of everything.

I will post my results soon.

There is all sorts of information in the Apple 'Console".

If one can get the infomation from there ..

But if you can't even start up ... no good.

I installed Lion and everything was fine for a couple of days.  My screen just went blank while performing normal activities.  I powered down and back up.  I had the sign in screen but without the password box, and I had the spinning color wheel.  There it stayed forever.  I followed  the adviice by rkaufmann87 above, and that did indeed save me.  Thanks!

Your welcome, glad it worked!

Same situation for me, gray screen with "You need to restart your computer.  Hold down the Power button until it turns off, the press the Power button again." It restarts to the same screen though, every time. Pressing Option while restarting offers only the choice of the usual boot up disk and the. The gray screen comes back. I don't have $49 to spend on real phone support. What do I do?  This is so frustrating!

Hi MJ,

You realize you woke up a 5 month thread, which I just happened to still be subscribed to.  What you are experiencing is a kernel panic.

Read up on it, and start a new topic thread with the status of any backup.  If none, say so, and someone can help you recover data, and then see if you have a hardware or software issue.  My link*

http://www.macmaps.com/kernelpanic.html should help.