The Quasi-Clean Installation The Completely Clean Installation Q & A 1. Introduction to Mac App Store Distribution of Lion Availability First things first, as we noted in our post earlier today, Apple ...

Apple has rolled out the fifth public beta of macOS Tahoe 26, ahead of the official launch next month. Here's what's coming.

Read about how to do that here: How to dual-boot Mac: Run two versions of macOS on a Mac. Alternatively, you could install the macOS beta on an external drive and run it on that.

If this is an Xserve server, be sure to unlock the drive lock so you can mount the installation disk. Insert the install disk and click on the “Install Mac OS” icon.