2020 date limit

The 2020 date limit is a date-related software bug that is triggered in Macintosh computers running Mac OS 9.0.3 (or earlier) on January 1, 2020 and onwards.

Though Apple's classic Hierarchical File System can manage dates up to February 6, 2040, the Date & Time control panel prior to Mac OS 9.0.4 is incapable of setting dates past December 31, 2019. An early workaround was to download Rob Braun's SetDate utility. In April 2020, a method to patch the bug was published on a blog.

Apple addressed the 2020 issue with the an updated control panel in Mac OS 9.0.4. In September 2017, the introduction of the Apple File System (APFS) in macOS 10.13 addressed the 2040 date limit.