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Debugging the Millennium Bug

NCJ Number
Date Published
1 page
This article, which was published in the spring of 1999, suggests a strategy for avoiding and/or addressing computer-related problems occasioned by dating codes that cannot correctly read the year 2000.
Forty years ago, computers were designed to use a standard programming language called COBOL, which stored data on Hollerith cards that had only 80 columns for information. To maximize the use of space, programmers shortened the designation of a year from four digits to the last two, which means that computers may not recognize 00 as indicating the year 2000 or will read it as 1900. This confusion may either abort computer systems or produce erroneous data. The problem has been called the Y2K (Year 2000) Problem. This article advises that if there is computer software that operates based on the day of the month or the year, or if the date had to be programmed into the computer when it was purchased, then it is vulnerable to a malfunction when the year 2000 arrives. The problem is compounded when computers are hooked into a network in which the operation of one computer depends on the correct operation of other computers in the network. Y2K assessments should determine what systems or equipment can fail and not cause undue harm and which ones will cause problems if they fail. The assessment should also determine whether there is a "patch" or "work-around" that can be used if needed. Vendors should be requested to provide Y2K certification and an assessment of what needs to be replaced. Prior testing of critical systems is imperative. A contingency plan should be developed to include strategies should internal systems fail.

Date Published: January 1, 1999