Y2K info for MS-DOS


All versions of MS-DOS numbered 5.0 or higher have the same level of Y2K compliance, and the same problems. You can determine which version you have by typing ver at a DOS prompt.
MS-DOS recognizes and properly sorts dates beyond 1999, up to December 31, 2099 (although Microsoft indicates that the operational range of date data in DOS only goes to the year 2035). the MS-DOS command dir displays dates using the format mm-dd-yy, so the date January 3, 2000 would be displayed as 01-03-00.
The MS-DOS date function assumes that all two-digit years occur in the 20th century, but it only recognizes the years 1980 and later as valid; entering a two digit year from 00 to 79 will result in an "Invalid date" error. To enter years past 1999, you must use all 4 digits (even though the date command prompts for a date in the form mm-dd-yy). For instance, entering the date 1-3-00 at the DATE prompt will result in an error; but entering 1-3-2000 will correctly set the date to January 3, 2000.
The program msbackup (provided with MS-DOS versions 6.x only) does not display dates after 1999 correctly. According to Microsoft, this is a problem with the user interface only, and does not prevent the program from properly handling backup sets.

More detailed information is available at:
Microsoft's Y2K pages for MS-DOS 6.22
Microsoft's Y2K pages for MS-DOS 6.0
Microsoft's Y2K pages for MS-DOS 5.x
Back to Y2K Links for DOS/Windows PC's
questions, comments, or suggestions?
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