flamebliss wrote:
yes wen i try booting in Safe Mode it behave the same. i have downloaded the combo update of 10.7.5 from another laptop, so how do i run it on my mac. THANKS for helping
The goal is to mount the combo update .dmg on the desktop and then open and run it. If you can't get to the desktop to begin with, that won't work. Another approach is to treat the Mac's hard disk as just another HD by using a second Mac and then connecting the problematic one via Target Disk Mode. See http://support.apple.com/kb/ht1661. Note that both Macs will need Firewire ports and you'll need a FIrewire cable to connect them. With the combo updater, one of the steps in the process is to select the drive you want to install the update on. Once you're successfully connected in Target Disk Mode, the problematic drive should appear in the list.
If that doesn't work or Target Disk Mode isn't possible, the only other solution is to boot into Recovery Mode; see http://support.apple.com/kb/ht4718. Note that once booted into recovery mode, you have access to Disk Utility, and you should try running Repair Disk after selecting the bad drive to see if something's wrong with the directory which could be fixed. When you select that drive, you should also look at S.M.A.R.T. Status at the bottom of the window. It should say "Verified." If it says Failing or Failed, the HD needs to be replaced.
If the HD is OK, all that's left that I can think of is to reinstall Lion using Recovery Mode. 😟 I hope you've maintained current backups or at least complete Time Machine backups. Of course, if you have a backup and the backup is bootable, you could boot from that, wipe the internal HD clean, and clone the backup onto the internal HD.