I'm having issues booting up my MacBook Pro. When I turn it on, I get the sound and the apple logo with the spinning wheel, then a loading bar appears, then after about 30 seconds it shuts off. Suggestions?

Question

I believe it's OSX 10.7.5 or .4, can't check now. I'm not able to boot up past the login screen. A bar comes up below the apple logo as if it's installing an apple update, but doesn't make any progress. Eventually, the bar goes away and just the apple logo and spinning wheel are there, then it just shuts off soon after. I've tried holding shift key on power up to enter safe mode, but nothing happens.  Any help/ suggestions would be greatly appreciated. Thanks!

Answer 1

You can't backup without booting the computer unless you remove the drive. But it may be you have a more serious hardware problem, so I think you may be better off taking it in for service.
But here's what you might try since you now have an external drive.
Repair the Hard Drive and Permissions - Lion/Mountain Lion
Boot to the Recovery HD:
Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
Repair
When the recovery menu appears select Disk Utility. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your drive's main entry (topmost one) and click on the First Aid tab, then click on the Repair Disk button. This will fix the boot block if it's damaged. Next, select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported then click on the Repair Permissions button.
If you have no problems with the above, then quit DU and return to the Main Menu. Select Restart from the Apple menu. See if the computer will boot properly.
If you get this far you should backup the drive ASAP. You will need to prepare your external drive:
Drive Preparation
1. Open Disk Utility in your Utilities folder.
2. After DU loads select your hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Click on the Partition tab in the DU main window.
3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Click on the Options button, set the partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Partition button and wait until the process has completed.
4. Select the volume you just created (this is the sub-entry under the drive entry) from the left side list. Click on the Erase tab in the DU main window.
5. Set the format type to Mac OS Extended (Journaled.) Click on the Security button, check the button for Zero Data and click on OK to return to the Erase window.
6. Click on the Erase button. The format process can take up to several hours depending upon the drive size.
Steps 4-6 are optional but should be used on a drive that has never been formatted before, if the format type is not Mac OS Extended, if the partition scheme has been changed, or if a different operating system (not OS X) has been installed on the drive.