Leopard Cannot Validate Base System

I had just installed a couple of 2GB Crucial sticks of RAM and then tried to install Leopard. I received the "Base System" error at the beginning of the install, before the install was done calculating the time remaining.

I pulled out the 2GB sticks and tried the install again. Leopard installed perfectly. I then added the RAM back in and tried to do Software Update. Long story short, the system crashed and the fans fired up. It sounded like a jet engine.

So, I pulled out the Crucial RAM and tried the update and this time it updated just fine. Since the RAM is brand new, I will definitely be asking for a replacement.

Not much help here, but I'm in the same boat. Slight difference is that I get the 'Base System' error before the installer finishes calculating the remaining time.
My machine is a G4 DP 1GHz MDD w/1.75Gig of RAM, USB 2.0 card & 3 HDs.
First I tried to upgrade the Tiger install on the original HD. Got the error "cannot validate 'Base System' package" error. Same error after erasing the main HD, removing all USB/Firewire devices other than keyboard/mouse, removing a PCI USB 2.0 card, removing non-Apple RAM, and trying the install on one of the other HDs (had to preserve one good working copy of Tiger on the machine).
Thinking about disconnecting the second Optical drive (an Apple CD-Rom drive from a B&W G3) and the additional HDs and try again.
2 notes:
1. I was able to install Tiger on the machine w/o issue with all my normal peripherals connected.
2. I was able to install Leopard on my iMac Core2 duo 2.16GHz using the same installer disk w/o issue
Any ideas are appreciated

Same problem here and I tried all the same things other user's indicated. Upon the suggestion of Apple Support - I shut down the iMac & removed a 3rd part RAM module. Then I put the Apple RAM module into Bank 0. Started computer. Started install over again.

Leopard installed is running well. All programs seemed to be operating.

On a possible related issue: I completed several MAC software updates and then I re-installed the 3rd party RAM. Curiously when I tried to complete another MAC software update after installing the 3rd party RAM they failed to complete - 3 times. They are still available as updates but will not complete.

Both RAM modules were reported by Profile as being just fine. No errors. All looked good and still does.

Suggest you remove any 3rd party RAM and try installing Leopard over again.

I will have to remove the 3rd party RAM again and see if the MAC software updates work again!

Message was edited by: Keemosaby

Message was edited by: Keemosaby

Message was edited by: Keemosaby

Tried the "base install" only, but got the same issue...

Had to try a few different sticks of RAM, but finally found one that the installer liked - dumbest install issue I've ever run into.
Thanks for the help!

Mike Foley wrote:
Had to try a few different sticks of RAM, but finally found one that the installer liked - dumbest install issue I've ever run into.
Thanks for the help!

I have to ask how a "normal" user would deal with this problem. You know, the guy who simply buys Leopard and gets this problem?
I can't wait to install Leopard on my G5. I need the exercise, mentally and physically 🙂
One day, in the not-to-distant future, this will all be ironed out. And then OS-X.6 will come out 🙂

I have had the worst night I have ever had with a Macintosh.

The system in question is a 15" MacBook Pro (Core Duo version) with 1 GB of RAM and an 80 GB hard drive. This is a completely stock system with no third party memory.

My system is so hosed that I can't even get Tiger running again. I'm recovering the disk to my G5 tower which will NOT be upgraded any time soon after this little debacle. That seems to be working.

I got the same error described here. Honestly it acts like a disk error. Once I have a reliable backup I am going to try blowing the system away (BIG pain in the rear due to software re-installs) and trying it one more time. If that doesn't work the whole lot is going back to the Apple Store and someone is fixing this somehow.

We bought a family pack and my wife installed Leopard on her current model iMac with problems whatsoever.

Looks like Apple either sent the wrong version out the door or someone really screwed up the release testing. This is really awful. I didn't have this much trouble moving from the old OS 9 to OS X!!!

You might be to far gone with your Tiger install but maybe this will help others.

1 Make a clone of your drive with Carbon Copy Cloner.
2 Do a clean install.
3 When you restart, use the Migration Assistant to reinstall all your software, accounts, settings etc. from your cloned drive back to your computer with the new Leopard install.

ncianca wrote:
You might be to far gone with your Tiger install but maybe this will help others.

1 Make a clone of your drive with Carbon Copy Cloner.
2 Do a clean install.
3 When you restart, use the Migration Assistant to reinstall all your software, accounts, settings etc. from your cloned drive back to your computer with the new Leopard install.

And preferably partition the external drive GUID before cloning so you can also boot it if you want to use your old OS intact.

I'm having the same problem - except that the error occurs early in the installation process - and now I can't even reboot using Tiger! So my almost-new iMac is a paperweight. Thanks, Apple.

Let's see. I tried installing 10.5 on a completely different drive than 10.4 in my G5. I was impatient and skipped the DVD test and of course, it failed. The real kicker is it has some how affected the Tiger install and when I try to boot my computer just shuts down right after the initial white "apple" screen.

Sounds like you are trying to boot of the disk that has an incomplete 10.5 install. Have you tried reseting the Power Manager?

http://docs.info.apple.com/article.html?artnum=14449

i have the same problem but i cant put the apple ram back in my macbook because i threw it away? is there another way to install leopard without the apple ram