System 6.0.6

System 6.0.6 (Finder 6.1.6, System Software Update 6.0.6) was never fully released, as internal testing revealed an AppleTalk bug.  It was slated for release on October 15, 1990 with added hardware support for the Macintosh LC, IIsi and Classic, but was superseded by System 6.0.7 which was published later the same day with AppleTalk fixed.
==References==
*Macintosh: System Software Version History (through 7.5.3) at Apple Support (2012-02-19)
*MacBulletin: Apple Pulls System 6.0.6, Macworld p.17. 1990-12.
*System 6.0.6 at Mac512 (archived 2016-12-02)
==See also==
*Mac OS 9.0.1
==External links==
*Older Software Downloads (System 6 and 7) at Apple Support (archived 2006-04-27)
*System 6 Heaven (archived 2017-02-21)
Category:Classic Mac OS development
Category:Unreleased Apple software