System 4.1

System 4.1, Finder 5.5 (System Software 2.01)

Mac users had just a month to enjoy a nice 1 digit version number of their Mac OS. System 4.1 was released the following month newly adapted for AppleShare 1.1. AppleShare 1.1 was needed to network the newly released Mac II, and an updated version of the Mac OS was needed to accommodate it. Another update due to new technology was the way the Finder handled large capacity drives (namely those larger than 32 MB). This System also excluded a model, the Mac 512k, since you needed 1 MB of RAM to run it. This was the last time Apple did that for a while though, since they would not exclude models from running a version of the Mac OS for over ten years later, with the introduction of Mac OS 7.6.


 * Released: April 1987