Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

External HD Boot fails with Snow Leopard

When I try to boot from an external HD with 10.6 installed I get a kernel panic "unable to find a driver for this platform". My internal drive has 10.7 installed. Any suggestions as to how to resolve the issue?


Here's a bit of background. I have some files on my computer that are produced by applications no longer supported on the Mac. They worked fine under Rosetta with 10.6 but when I upgraded to 10.7 and Rosetta was dropped, so did my ability to access the files. I'm really keen to be able to at least open the files and see if I can export them to useful format, or even print them.


Today I purchased an external 1TB HD in the hope that this would solve my problem. I intended to boot up using Snow Leaopard. I installed it using the DVD purchased as part of the Mac Boxed Set a while back. There are two partitions on the HD, a 50GB section with 10.6 on it and a 950GB which is blank.


When the installation was complete the Mac automatically rebooted. Unfortunately it panicked midway through the restart. I've tried re-initialising the drive and checking the firmware. Everything seems ok there. I'm not sure what to do next.


Peter

iMac, Mac OS X (10.7.3)

Posted on Mar 17, 2012 4:42 AM

Reply
23 replies

Mar 17, 2012 8:08 AM in response to peterpumpkin

Did your iMac come preinstalled with 10.7 or did you update from 10.6 to 10.7....?


Here's the thing, Snow Leopard will not run on a new iMac that shipped with Lion.


see > Don't install a version of Mac OS X earlier than what came with your Mac


If however your iMac is pre-Lion, then perhaps you have not properly setup the External Hard Drive (GUID Partition Table / Mac OS Extended (Journaled) so that the Intel iMac will boot from it...?


see > OSX Tips: Using Disk Utility 1. Format, Erase, or Reformat a Drive

Mar 17, 2012 3:13 PM in response to peterpumpkin

A Mid 2007 originally came with Tiger and a Early 2008 came with Leopard, but that's not all that important in this case.


Is that Snow Leopard Install DVD a white Retail Upgrade DVD or a gray System Specific Install disc for a different iMac?


If it is gray, please note that the system specific disc sets only support the orignal iMac model that they shipped with.

Mar 17, 2012 3:18 PM in response to peterpumpkin

Today I purchased an external 1TB HD in the hope that this would solve my problem. I intended to boot up using Snow Leaopard.


Assuming you formatted as Mac OS Extended, journaled, GUID partitioned, it may be that the enclosure itself is the problem. Some enclosure bridge firmware are not necessarily compatible with all models of macs.


Are you using firewire or usb to the enclosure? If it supports both try the other kind.


As an additional experiment clone your current boot drive on to the external using, say, Carbon Copy Cloner. See if that will boot.

Mar 17, 2012 9:51 PM in response to peterpumpkin

Well, the clone didn't work. I copied the following files/folders to the external as advised by CCC:

/Library, /System, /bin, /etc, /mach_kernel, /private, /sbin, /tmp, /usr, and /var


There was a panic on startup with the following info displayed:


panic(cpu 1 caller 0xffffff7f807b1f9a): "No HPETs available...CPU(s) configured incorrectly\n"@/SourceCache/AppleIntelCPUPowerManagement/AppleIntelCPUPowerMana gement-167.3/pmThread.c:156

Backtrace (CPU 1), Frame : Return Address

0xffffff807987bef0 : 0xffffff8000220702

0xffffff807987bf70 : 0xffffff7f807b1f9a

0xffffff807987bfb0 : 0xffffff8000820057

Kernel Extensions in backtrace:

com.apple.driver.AppleIntelCPUPowerManagement(167.3)[E08EC0D7-C364-3C57-A377-88 7B36241B1C]@0xffffff7f807ac000->0xffffff7f807d5fff



BSD process name corresponding to current thread: kernel_task



Mac OS version:

Not yet set



Kernel version:

Darwin Kernel Version 11.3.0: Thu Jan 12 18:47:41 PST 2012; root:xnu-1699.24.23~1/RELEASE_X86_64

Kernel UUID: 7B6546C7-70E8-3ED8-A6C3-C927E4D3D0D6

System model name: iMac8,1 (Mac-F227BEC8)


I will try installing a copy of the 10.6.3 operating system on my firewire HD and see if that works.

Mar 17, 2012 11:40 PM in response to X423424X

I know nothing but just restored from my 10.6 crash and reformatted a 500. gig and a 80. gig western digital portable HDD from walmart ,


they both checked out as fine and for a week trying around the clock at times kept freezing, I even was able to replace the original drive internally with them to try booting up,


As I actually had given up and decided to purchase a drive with 10.6 installed?


But could not resist another try and amazed to my situation it loaded and booted on the 500. G WD drive off the !).^ DVD


And with the 80. g I ran time machine long enough to complete 3 back ups


During the first 45 minutes running updates, with 3 hours of them I managed almost the first hour before it froze.


I am waiting for some help with managing what I have so far, but just to share I too have had difficulties loading the 10.6 to reboot


(loading the 10.6 was no trouble, booting it up has been.


Hope you don't mind me cutting in, I am looking for clues myself. Thanks

External HD Boot fails with Snow Leopard

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple ID.