Install Disk for Snow Leopard will not boot on an iMac 27in

According to https://discussions.apple.com/docs/DOC-2455 you can install 10.6.x

As the original OS would have been 10.6.6 or 10.6.7 (probably 10.6.6 for a May model), there should be no problem installing and remaining at 10.6.7.

Note that the retail 10.6.3 won't work - to install from a DVD, it'll have to be the ones that should have shipped with the Mac (builds 10J4026 or 10J4139). The same build restriction will apply to TGM install, too.

Thanks so much for the quick reply. This is very helpful. I'll give an update after I try it.

hi

just reading your comment-

as i am trying to get back to SL and bought a black macbook with LION...which i absolutely hate!

i was wondering how i did this as i dont have any grey installation discs....yes its an intel macbook core 2 duo

so no discs....does anyone here have their grey install discs i could borrow please?

i have an ibook....and i know zero about this...so i even foolishly tried ppc discs (grey) on this macbook...obviously it spat them out with the 'wont play ppc discs...' etc warning.

so any help please....im so annoyed and a tad stressed as LION makes my cpu heat up just watching you tube clips! its insane.

my little ibook is my work horse and the cpu rarely ever kicks in as it doesnt over heat.

sniff....so sad 😟

CarolineUK

It would have been better to start another thread, Caroline.

However, now you're here -

The original OS for the black MacBooks would have been either Tiger or Leopard.

There's an outside chance you could get copies from Apple Customer Services. Try calling them with the serial no. of the MB.

The original discs have both the Apple Hardware Test for that model, and the bundled applications - iMovie, iDVD, iPhoto and GarageBand.

In the meantime, to get to Snow Leopard you're going to need a retail install disc; you're also going to need at least one external Hard Drive, preferably FireWire. To begin with, use the external to back up your Lion installation in case of problems. Kappy gives a link to CCC near the end.

Courtesy of Kappy from an earlier thread - this method should work OK if the Lion firmware update hasn't been installed;

"Downgrade Lion to Snow Leopard

1. Boot from your Snow Leopard Installer Disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu.

2. After DU loads select your hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Note the SMART status of the drive in DU's status area. If it does not say "Verified" then the drive is failing or has failed and will need replacing. SMART info will not be reported on external drives. Otherwise, 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. Set the format type to Mac OS Extended (Journaled.) Click on the Options button, set the partition scheme to GUID then click on the OK button. Click on the Partition button and wait until the process has completed.

4. Quit DU and return to the installer. Install Snow Leopard.

This will erase the whole drive so be sure to backup your files if you don't have a backup already. If you have performed a TM backup using Lion be aware that you cannot restore from that backup in Snow Leopard. I suggest you make a separate backup using Carbon Copy Cloner 3.4.1."

Try that first. If it fails, it's most likely because of a firmware update. There's a way round that, too, but it's more involved, so try the straightforward approach first.

Hey there NDW.....

I am long time mac user but new to this Forum.

Like others here i've had demonsterous problems

trying to downgrade my imac from SL to lion. (it was shipped with lion)

I've tried all ways round it and with no sucess i accept defeat.... (**** It)

My only question is of wiser powers such as yourself....

How do i get it back to LION ?

Now my imac wont go past "white screen with grey apple logo" ......

to put it in simply !

*** is going on ?

I really admired lion's up untill now...

Any help most welcome...

J.

PS: just read that 10.6.3 does not work, this is the os ive been trying to install

(downgrade from 10.7.0)

Still i need a "get out of jail free card" to get it running again on lion.

any ideas.....

And why did apple do this ... ship mac's with no os disc's & all ready to go etc

Are we as a human race so ..... dumb ... that we cant DIY anymore ?

Frustrating at the least.

J.

Hi Jase Be,

Have you tried holding the ALT key down on boot up, and selecting "choose network" logging on to your wifi and downloading Lion direct form Apples servers?

I don't personally use Lion, which is I was quoting Kappy (who does).

However unless you've completely wiped the HD, you ought to be able to boot to the recovery partition by starting with the cmd and R keys held down (⌘R) and re-download Lion from there.

AS for SL, it depends what model your iMac is as to whether there's a possibility of installing it. See a.brody's article; https://discussions.apple.com/docs/DOC-2455 to identify if yours will.

It's unlikely you'd be able to do so from the disc, even the one that would have shipped with it prior to Lion, as a firmware update seems to have b••••••d that route.

However, provided the Mac is not precluded from doing so, you should be able to install from the 10.6.3 retail disc to an external HD and update that to 10.6.8 and use that to boot from.

See Kappy's post here; https://discussions.apple.com/thread/3659568?answerId=17330084022#17330084022

hi,

did you manage to downgrade?

I managed to downgrade from Lion to Snow Leopard using the installation disk which i had to buy from Apple for£17...as i bought the MB second hand...with bloomin Lion on it!

At first it didnt work saying that the OS couldnt be installed on the computer.

So I followed the instructions from the user Moondayswitch (above)..you basically have to partition the HD and by miracle, SL installed on the macbook..

So you can do it!

You wouldn't believe what I had to do.

I installed Snow Leopard on an external hard drive the same size as the one in my 27" iMac from a computer that could boot the disc. I then updated to 10.6.8.

I then hooked that drive up to my iMac, booted into my Lion disk utilities and used the restore tool to copy the external hard drive to my internal one.

It took all day... in fact... my disc is still restoring as it takes about 12 hours to restore 1TB from one drive to another.

I am glad that I have found this thread (which is covering more then 2 years, but who cares ;-). The information in it is very valuable to me.

I finally realize after a half a day of fiddling and wasting my time thinking that there was some kind of disk reading problem that there actually is a minimum OSX version needed when reinstalling OSX depending on the Apple product! In my case, it was driving me nuts why I could not start the DVD that came with my older MacBookPro to freshen up my girlriend just-al-little-newer MacBook Pro nor an external drive with a 1:1 copy of the disk (using SuperDuper).

This now demystified issue could be prevented by Apple by implementing a little bit of user interfacing with the one that "accidently" inserts an OSX installation/recovery disk! Something like: This Mac requires at least OSX version 10.6.3, you have inserted 10.6.0 would cut it.

Wouldn't matter - you'd still have to buy a retail version of the OS. You cannot install OS X from a DVD which shipped with one Mac model onto another Mac model, regardless of relative age. The discs are (deliberately) model-specific.

I have just found this fix for this issue.

Very cheap - & I would say a legitimate workaround, that provides a final solution.

I bought a refurbished iMac 27" (from May 2011) & it came with Lion and no discs. I know this mac will boot snow lepoard but not earlier than 10.6.7 (or.6 maybe).

Anyway, Apple are now selling retail Snow Leopard for $20.99 (I'm in Australia so that's AUD). It's called archive sales and only available by phone purchase now (again, that's in Aus, might be different elswhere).

Ok this is only 10.6.3 BUT...

***use this excellent hint... http://hints.macworld.com/article.php?story=20120123175902871 and problem solved, bootable 10.6.7 installer!

You will need the retail disk, a copy of the 10.6.7 install disk from any other computer and minimal tech savvy (the instrucitons are very clear and simple), and an 8GB or larger USB stick...

I'm at the carbon copy cloner stage now, so all going to plan I should be running Snow Leopard by this evening.

Thanks to those helpful folk at MacOS hints.

hope this helps somebody else in my position.

cheers

*Oh and check here to see if your mac can run SL