Article · Wikipedia archive · Last revised Jul 26, 2026

XPostFacto

XPostFacto is an open source utility for Mac OS 9 that enables the installation of PowerPC versions of Mac OS X up to Mac OS X v10.4 (Tiger), and Darwin on some PowerPC-based Apple Macintosh systems that are not officially supported by Apple. It was released in 2002.

Last revised
Jul 26, 2026
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XPostFacto is an open source utility for Mac OS 9 that enables the installation of PowerPC versions of Mac OS X up to Mac OS X v10.4 (Tiger), and Darwin on some PowerPC-based Apple Macintosh systems that are not officially supported by Apple. It was released in 2002.1

Functions

XPostFacto allowed Darwin, OS X, and OS X Server to run on unsupported Mac models. The OS X Installer would not run on machines without a G3, G4, G5, or Intel processor by default, but XPostFacto patched the installer to allow it to run.2 A Mac OS 9 partition must be booted first. XPostFacto then runs in Mac OS 9 using an installation CD to install a version of OS X.34

XPostFacto is available for free, but the company offered support for either $10 or $25.53

Supported models

XPostFacto 4.0 works with pre-G3 Macintosh models.2 Beige box Power Macs as old as upgraded 7300-era machines are supported.5 Limited support was also available for Performa 6400, 6500 models and Twentieth Anniversary Macintosh with PowerPC G3 upgrade card.6

Reception

Engadget questioned the utility of XPostFacto, stating "OS X runs like a limp turtle on our old iMac G3."7

External links
References

References

  1. Frakes, Dan (2006-07-14). Mac OS X Power Tools. John Wiley & Sons. ISBN 978-0-7821-5192-3.
  2. Pogue, David (2005-07-12). Mac OS X: The Missing Manual, Tiger Edition: The Missing Manual. O'Reilly Media, Inc. ISBN 978-1-4493-7907-0.
  3. Dornfest, Rael; Hemenway, Kevin (2003). Mac OS X Hacks. O'Reilly Media, Inc. ISBN 978-0-596-00460-6.
  4. Stern, Hadley (2004-10-13). IPod and ITunes Hacks: Tips and Tools for Ripping, Mixing and Burning. O'Reilly Media, Inc. ISBN 978-0-596-00778-2.
  5. Cohen, Peter (2005-10-14). "XPostFacto 4.0 supports Tiger on older Macs". Macworld. Retrieved 2024-05-06.
  6. "Utilities Updates: InterView; XPostFacto; MacInstall;". CNET. 2009-10-01. Retrieved 2024-05-06.
  7. Blass, Evan (2005-09-16). "XPostFacto to shoehorn Tiger into every Mac ever built". Engadget. Retrieved 2024-05-06.