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2001 Mac OS 9

2001 Mac OS 9.1 (Fortissimo)

Mac OS 9.1 was released on January 9, 2001, and was available either as a 71 MB update (either in one piece or as separate segments) or as a "full install" version (which was the only version that worked for users of language kits).

This was the last version of the Mac OS that ran on any PowerPC-based Macintosh. Future versions, including Mac OS 9.2, Mac OS 9.2.1 and Mac OS 9.2.2, as well as Mac OS X, would require -- at least -- a PowerPC G3 processor (except for the original PowerBook G3 and upgrade cards).

What's New[]

  • Mac OS 9.1 is much improved in terms of overall speed and stability; the Finder, as well as switching between applications, is markedly faster.
  • The Applications folder has been renamed Applications (Mac OS 9), obviously in anticipation for Mac OS X. Previously standalone folders, such as Utilities, Internet and other folders, are moved or removed. (Most of them are ultimately moved.)
  • Keyboard shortcuts have been improved; there are now shortcuts for emptying the Trash (Wastebasket), View Options, and Add to Favourites.
  • In the General Controls control panel, the Folder Protection preference has been removed. The Shut Down warning (in case the Mac was unable to restart or shut down normally) has been reworded to say Check Disk in case the system was not shut down properly. The new version of the General control panel also allows each user (in multi-user mode) to set their own preferences (for cursor, speech, and default folder options).
  • There was a minor improvement in Get Info windows which now permit freer editing of memory settings (it is now possible to make changes to any fields without the Finder warning about invalid memory configurations.
  • iDisk integration is deeper; the "Connect to iDisk" option is a new appearance in the Network icon of the new Navigation Services open and save dialogue boxes.
  • The Process Manager is now in native PowerPC code.
  • Sherlock 2 is now in the Applications (Mac OS 9) folder, with an alias in the Apple menu. The Entertainment channel is also a novelty.
  • The improved Sound control panel now sports a signal level meter.
  • The Startup Disk control panel got a huge redesign (to ease the transition to Mac OS X).
  • USB Printer Sharing is now installed as part of the standard Mac OS.
  • A Window menu now lists all open Finder windows.
  • Data CD burning directly from the Finder


  • The Mac OS X Public Beta is incompatible with Mac OS 9.1. (If Mac OS 9.1 is installed, the Classic environment in Mac OS X Public Beta will no longer function.)
  • PowerBook 3400s running Mac OS 9.0.4 must upgrade directly without updating hard disk drivers, or the installation may hang.
  • Password Security is not supported on PowerBook 1400s under Mac OS 9.1. Disable password protection before installing Mac OS 9.1.
  • Language kits were included beginning with this version of the Mac OS. Both the system software and the language kits must be updated at the same time.
  • ATM Deluxe version 4.5 is incompatible with WorldScript I. If you use Arabic, Hebrew, Devanagari, Gurmukhi, Gujarati or Persian language kits, upgrade to version 4.6 or later.
  • A GX desktop printer set up on the hard disk may entail a crash during installation. Drag the GX desktop printer icon to the trash before installation.
  • Installing Mac OS 9.1 on a Twentieth Anniversary Macintosh with Virtual Memory on may result in a crash. Switch off Virtual Memory before installing Mac OS 9.1.
  • Owners of a Power Macintosh 6100, 7100, 8100 or 9150 with a third-party accelerator card that increases the speed of your computer, Mac OS 9.1 may not install at all. Contact the accelerator card's manufacturer for help.

External links[]

Mac OS 9
Mac OS 9.0 | Mac OS 9.0.1 | Mac OS 9.0.2 | Mac OS 9.0.3 | Mac OS 9.0.4 | Mac OS 9.1 |
Mac OS 9.2 | Mac OS 9.2.1 | Mac OS 9.2.2 | Classic environment
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