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Two editions of Windows 2.10 were released, both of which could take advantage of the Intel processor for which they were designed.

Windows2.1 /286
Windows/286 takes advantage of the HMA to increase the memory available to Windows programs. It introduced the himem.sys DOS driver for this purpose. It also includes support for several EMS boards, although this support is not related to the 80286 processor. The segmented nature of Windows programs is quite suited to the usage of EMS, as portions of code and data can be made visible in the first megabyte of memory accessible to real-mode programs only when the program using them is given control. Microsoft encouraged users to configure their computers with only 256KB of main memory, leaving the address space from 256-640KB available for dynamic mapping of EMS memory.

Despite its name, Windows/286 was fully operational on an 8088 or 8086 processor. Windows/286 would simply not use the high memory area since none exist on an 8086-class processor; however, EMS could still be used, if present. A few PC vendors shipped Windows/286 with 8086 hardware; an example was IBM's PS/2 Model 25, which had an option to ship with a "DOS 4.00 and Windows kit" for educational markets, which included word processing and presentation software useful for students, which resulted in some confusion when purchasers of this system received a box labeled Windows/286 with a machine that was definitely less than an 80286.