From The Apple Wiki
< Firmware‎ | Mac

Releases of Mac OS X prior to Mavericks were paid upgrades. As such, full installers mostly do not exist for these versions. Apple made exceptions for Mac OS X Lion and OS X Mountain Lion, which were released as a free download on the Apple Support website on 2 July 2021. On 24 October 2019 and 10 February 2015, in preparation for an Apple Software Update certificate expiring causing installer packages to display an integrity error and refuse to install, Apple reissued many updates, signed with a new certificate.[1][2]

To install copies of macOS without updated certificates, change the Mac's system clock to sometime prior to 24 October 2019 before attempting installation, and reset it to the current date afterwards. If the Mac doesn't have an existing operating system installation, this may be done from the installation environment by clicking Utilities → Terminal, then entering date 1001000019 to set the date to midnight on 1 October 2019. Press ⌘Q to quit Terminal and return to the installer.

Most downloads are a patch updater (upgrading directly from the previous version), or combo updater (upgrading from any earlier version in the same major release). To perform a clean installation of macOS, use a full release build.

Version Build Release Date Download URL File Size Documentation
10.3 7B85 24 October 2003 Paid Release Security Notes
10.3.1 7C107 10 November 2003 MacOSXUpdate10.3.1.dmg 985,829 Release Notes
Security Notes
10.3.2 7D24 17 December 2003 ? ? Release Notes
Security Notes
7D28 ? ? ?
10.3.3 7F44 15 March 2004 MacOSXUpdate10.3.3.dmg
Release Notes
Security Notes
10.3.4 7H63 16 May 2004 MacOSXUpdateCombo10.3.4.dmg 82,872,975 Release Notes
Security Notes
10.3.5 7M34 9 August 2004 MacOSXCombo10.3.5.dmg 89,386,731 Release Notes
Security Notes
10.3.6 7R28 5 November 2004 MacOSXUpdate10.3.6.dmg 35,039,965 Release Notes
Security Notes
10.3.7 7S215 15 December 2004 MacOSXUpdateCombo10.3.7.dmg
Release Notes
Security Notes
10.3.8 7U16 9 February 2005 MacOSXUpdate10.3.8.dmg
Release Notes
Security Notes [Archived 2014-08-17 at the Wayback Machine]
10.3.9 7W98 15 April 2005 MacOSXUpdate10.3.9.dmg
Release Notes [Archived 2013-12-08 at the Wayback Machine]
Security Notes [Archived 2014-08-17 at the Wayback Machine]

See Also