kernel panic unable to find driver for this platform \acpi\

hi folks i need your help on this one. i updated the software (firmware update, itunes, safari, security and some others total of 8) and after reboot all i get is the gray screen to power off. on the screen it says panic- 7 lines of numbers that look like areas of the memory. below that it says mac os version: ot yet set.

what can i try to fix this problem. i have the osx cd's if i need to boot from cd.

thank you for your help and i will be reading up in this thread all day.

imac 24" 2.8 processor 2007?? leopard

should i try to reinstall osx?

this is what it says on the screen.

panic (cpu 0 caller 0x0043913f): unable to find driver for this platform: \ACPI\" .\in"@/SourceCache/xnu/xnu-1228.15.4/iokit/kernel/IOPlatformExpert.ccp:1407

Debugger called: <panic>

Backtrace (cpu 0), frame : return address (4 potential args on stack)

0x54dabdd8 : (SOME NUMBERS)
........BE28 : ....
..........BE48 : ....
........BEA8 : ....
........BF28 : ....
............78 : .....
..........C8 : ......
backtrace terminated-invalid fram pointer 0

BSD process name corresponding to current thread : Unknown

Mac OS version:
Not yet set

Kernel version:
Darwi9n Kernel version 9.8.0: wed jul 15 16:55:01 pdt 2009; root:xnu-1228.15.4~1/RELESE_I386

system uptime in nanoseconds : 156433694



if you need to know the numbers let me know ill type them up.
thank you.

thank you for suggesting to boot with shift key. after pressing shift it took almost 10 min. for it to start, and on the login screen it said in red that its "safe mode" i am logged in now. what can i try to fix the problem??? as i take it that if i dont boot up like this it will still give me the kernel panic.

ok thanks!
i copied what you posted there to this thread so other people can learn from it if they have the same problem.
ill read up about it there.



Hi,
you got 2 ways: reinstall your OS with Archive and Install option (you won't lose your data) or reinstall updates by installing combo update - this way: http://archive.macfixitforums.com/ubbthreads.php/ubb/showthreaded/Number/827659/site_id/1

ok thanks for your replies guys. with your help i was able to fix the problem.
what i did was log in while pressing the shift key, then went to apple and downloaded the osx 10.5.8 combo update, installed the update and restarted the computer to double check if it fixed it, and its loading up fine. thank you.