Help, I can't find the Mac OS 9 installer!
For Macs that came with 8.6 or earlier, but are being upgraded to Mac OS X 10.2 or later, it is necessary to purchase Mac OS 9 through the Up to Date program PDF file (requires Adobe Acrobat reader to read and print out). Mac OS 9 is not included on the retail OS X disks*. A simple install of Mac OS X, and not an erase and install is recommended if you are going to install Mac OS X 10.3.
* Mac OS X 10.0 and 10.1 retail versions included full install Mac OS 9 disks. Mac OS X 10.2 and later do not include any form of 9, other than the software necessary to run the Classic environment, but not the actual operating system itself.
For Macs that came with Mac OS 9.0 through 9.2.1, it is recommended you first clean install Mac OS 9 with the Mac OS 9 CD that came with the machine or a newer retail version* of Mac OS 9 and then upgrade to Mac OS 9.2.2 via these updates for the best compatibility in the Mac OS X Classic environment:
9.1, 9.2.1, 9.2.2.
* By retail version, that means the version that came on a white CD with an orange 9 logo,
and does not say Update CD.
If your Mac came with Mac OS X and restore CD or DVD chances are Mac OS 9 is already preloaded on your restore CD or DVD.