There are a few reasons why you might want to install an old version of macOS or Mac OS X. Perhaps you are relying on software you have discovered doesn’t work properly with the newest version of ...

If you have a spare hard drive lying around, you could use the existing recovery partition to install the OS on to that, even if just temporarily. If you have a friend with a Mac, he could download ...

macOS Monterey version 12 is a stable, lightweight upgrade that works great on older Macs, and you can use the direct DMG or ISO links to download, install, upgrade, or downgrade your system easily.

[Editor’s note: This article is part of our series of articles on installing and upgrading to Lion (OS X 10.7). We also have a complete guide to installing and upgrading to Mountain Lion (OS X 10.8).] ...

This warning should be heeded by all users attempting to install a fresh copy of Mac OS X, then use Software Update to upgrade to Mac OS X 10.2.5. If install any iteration of Mac OS X prior to version ...

Mac OS X 10.4.x (Tiger) ships, by default, on a DVD. This poses a problem for Macs shipped without a DVD drive, those with non-functional DVD drives, or those which have had their drives manually ...