Wednesday, May 24, 2023

The AARD Code and DR DOS

Geoff Chappell:

Some programs and drivers in some pre-release builds of Windows 3.1 include code that tests for execution on MS-DOS and displays a disingenuous error message if Windows is run on some other type of DOS. The message tells of a “Non-fatal error” and advises the user to “contact Windows 3.1 beta support”. Some programs in the released build include the code and the error message, and even execute the code, performing the same tests, but without acting on the result to display the error message.

Geoff Chappell (via Hacker News):

For roughly a year after I noticed on 17th April 1992 that the HIMEM.SYS driver from a Microsoft Windows 3.1 beta contained what eventually became known as the AARD Code, I had no idea which non-standard DOS had been affected.


By the late 1990s, the AARD code had no small role in a court case, Caldera, Inc. v. Microsoft Corp., 72 F. Supp.2d.1295 (D. Utah 1999), which Caldera, who was by then the owner of DR DOS after Digital Research and Novell, brought against Microsoft “for damages and injunctive relief under the antitrust laws of the United States, and for damages in tort”. The AARD code has ever since been for many some sort of pin-up for anti-competitive practices by Microsoft.


I, for the record, have tended to side with Microsoft on this: not on the general question of anti-competitive practices, for which Microsoft deserves far greater condemnation than the computer industry and various governments have allowed it to escape with, but on the AARD code specifically; and not then for the disingenuous error message and the code’s obfuscation, which I always thought childish and quickly also regarded as despicable, but for Microsoft’s general disposition to DR DOS.


Comments RSS · Twitter · Mastodon

Leave a Comment