In April 1984, following the release of the Macintosh, Apple introduced MacWorks, a software emulation environment which allows the Lisa to run Macintosh System software and applications. MacWorks helped make the Lisa more attractive to potential customers, although it did not enable the Macintosh emulation to access the hard disk until September. Initial versions of the Mac OS could not support a hard disk on the Macintosh machines. In January 1985, re-branded MacWorks XL, it became the primary system application designed to turn the Lisa into the Macintosh XL.