In the pantheon of computing history, the Apple Lisa is often remembered as the "noble failure"—the $10,000 business machine that was too expensive for the masses but too slow for power users. However, for collectors and vintage computing enthusiasts, Lisa Version 2.90 represents a fascinating and bittersweet milestone: the final and most mature version of the Lisa Office System before its transformation into the Macintosh XL. What’s New in System 2.90? Released quietly in late 1984, Lisa OS 2.90 was a maintenance and optimization release aimed at the remaining Lisa 2/5 and 2/10 owners. It wasn't a flashy update, but it fixed the rough edges that had plagued earlier versions. Here’s what it brought to the table: 1. The Death of the "Startup Delay" Previous versions (2.0 and 2.5) were notorious for a 20-30 second wait while the system loaded the Finder. Version 2.90 optimized the loading sequence from the new 400K or 800K disks, shaving nearly 40% off boot times. The machine finally felt responsive the moment the desktop appeared. 2. Mac-like File Management By late 1984, the Macintosh was winning the public's heart. Lisa 2.90 borrowed heavily from its younger sibling. The file manager received a cleaner, icon-based navigation system, including the ability to drag icons directly to the trash. The confusing "Stationery Pad" feature was replaced with a simpler "Duplicate" command. 3. Improved Memory Management One of Lisa's original strengths was its protected memory (each app ran in its own sandbox). Version 2.90 finally allowed users to adjust partition sizes without rebooting. It also introduced a "Low Memory Warning" dialog—a first for any Apple GUI. 4. Printer and Serial Fixes With the introduction of the LaserWriter, Lisa 2.90 included updated drivers for AppleTalk. While the Lisa couldn't run the Mac’s PostScript as smoothly, 2.90 allowed reliable serial connections to ImageWriters and early daisy-wheel printers without the frequent timeouts seen in 2.5. The "Lisa 2/10" Experience The hardware sweet spot for 2.90 was the Lisa 2/10 (512K RAM, internal 10MB Profile hard drive). With this OS, the machine felt like a completely different animal than the original Lisa 1. The hard drive became bootable directly from ROM, and the new "HFS" (Hierarchical File System) support allowed for nested folders—a feature early Lisas lacked. The End of an Era Why does 2.90 matter? Because it was the last pure-Lisa OS. Immediately after 2.90's release, Apple launched the MacWorks program, allowing Lisa owners to emulate the Macintosh. By mid-1985, Apple rebranded the Lisa 2/10 as the Macintosh XL and killed the Lisa Office System entirely.