Okay - here's another one in so many days which also has me completely stuffed nor do I have an inkling of a "why".

Okay... so I tend to do rounds of Apple Software Updates to keep.

Have downloaded the Mac OS 10.5.4 update as both the Combo Update @ 561MB, and the Delta Update @ 88MB - or something like that - for upgrade from 10.5.3 to 10.5.4.

So anyway, they both come down as regular .dmgs, but for some weird weird reason, when I attempt to upgrade, let's say, the latest iMac running 10.5.2 with the 561MB dmg, it comes up with a message - I haven't got a copy of it - that says something like:

This dmg cannot be used on this machine.

But if I open it and try it, another little bleeder comes along saying something like:

This version of Mac OS X cannot be installed on this machine.

I have re-downloaded them, and have it stored it to two different discs and to my trusty Pocket Clearlight, but... no bananas - and no - I'm not attempting to install it on the wrong machine.

If I go to the Software Update of any of these iMacs, there it is! Mac OS X 10.5.4 Combo Update - 561MB - the same thing... but it'll only update from Software Updates, and the idea here is to try to save "fools" with BigPond... or whoever offers crap Download limits, getting shaped or priced.

Wtf am I doing wrong?

ta

cw

Possibly the Pre-Intel Combo Update? Or it may be like the system discs that come with a particular machine. i.e. If I have a MacBook Pro with install discs, I cannot install that on an iMac.

Are you trying to install them from the disk?

I know that they get fussy about network installs, so perhaps try copying it from the disk and on to the computer then launching it.

So.... but... then that would mean there's a "secret" OS X upgrade on Apple for every model of new Mac?

Surely not...

I think not. I use a single download to update my iMacs and Macbook.

i can do that just fine

If you boot off the disc normally it will load, you can access disk utility but you can't install OS X. It comes up with some error message: You cannot install Mac OS X on this volume.

I mean - the one thing I haven't tried, chiefly because I can't for exactly the same reason, is to Install Leopard 10.5.4 on a partition of my Clearlight External, and then install either the .dmg or its opened Package from there.

However... I have Leopard 10.5.4 as a partition on my Clearlight, and although it does boot my Mac Mini Intel Core 2.0GHz, it won't boot any other Apple Mac...

PS: I don't like Leopard. I don't care how fancy it is. There is only the Mac Mini running it for test purposes, and I'd never put anything valuable there...

Seriously, I've tried installing all ways - copy from disc, copy from External Drive - and copying both as packages. It just spits the dummy each time. I'm only seeing this on the Mac OS X 10.5.4 Upgrade. It doesn't happen with QuickTime 7.5 or Security Update 2008-005 etc etc.

The problem also makes it impossible to post out discs to those who have low download limits, or are on dial-up. It has me stumped. Next time I do it, I'll take snap-shots...

Clockwork,
Like Deancorp suggested above, the only thing I can think of is that the updates are ppc and you're trying to use it to upgrade an intel Mac system - or vice versa.

But - I see that Apple are now releasing universal updates, no longer separate PPC or Intel versions. (not sure how recently this started) Are you sure your downloads are universal ?

Is the system on your clearlight a PPC or Intel one ?
I have partitioned my external and have both installed as I have a mixture of macs.
The Intel one you use to boot your Intel mac Mini won't start a PPC Mac.

The one thing I know for certain is that once you have current 10.5.4 PPC and Intel OSX systems installed on an external, you can start any mac newer than a G3.

Jim - another thing I tried... in my sneaky and underhanded way... was to download those big OS X Updates from the machines they were designed to Install upon, by choosing Download Only from Software Update...

So - I downloaded through a 20" iMac Intel Core 2 Duo, and then tried to install that download onto another 20" iMac Intel Core 2 Duo... and the result was no go, again.

That is why I'm getting all paranoid.

Definitely Universal.

Clockwork,
I thought when you download via software update, you only get the incremental update, not a combo. So unless the machines were already running 10.5.3 it wouldn't work.

I suggest to relieve the paranoia you start to re download a universal combo 10.5.4 update from Apples web site, and go and make a nice cup of tea and chill for 10, then come back and have another crack with a clear head. - If that doesn't work, then I can lend you some big hammers to smash the macs with.

These are customers, right?

Unlike folks who are proficient at keeping their macs up to date, they never... but never... pay any attention to the automatic Software Update alert - they always hit Cancel.

So they really are starting off from OS X 10.5.2.

And here's another I can't fathom.