By far, the most popular so-called DOS Extender in the early 1990’s was DOS/4GW. MS-DOS game compatibility occupied a very large portion of my time during Windows 95 development, so I saw a lot of DOS Extender banners, most frequently the DOS/4GW banner.
Now, you might wonder, “How did these games even run in Windows 95 if they came with a DOS Extender? Wouldn’t the extender try to enter protected mode and fail, because Windows was already managing protected mode?”
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