Did the Y2K Bug Actually Cause Any Problems?

The Y2K bug did actually cause many problems in the United States and around the world.  These problems weren't as widespread as many people expected them to be, but there were enough of them to make us realize that the Y2K bug was a real problem.  The most common problems which arose immediately in the United States were very inconsequential for all but a small portion of the population.  The majority of the problems related to the Y2K bug didn't occur as the clock struck midnight on December 31, 1999, but in the following days.  Below is a list of some of the bugs which were reported.  A nation by nation list compiled by the International Y2K Cooperation Center is available at can be reached by clicking this link: IY2CC List of Bugs



A survey of 51 school districts across the United States indicated that very few problems arose resulting from the millennium bug.  One district reported that some water heaters had to be turned on manually.  Another reported that computers were displaying incorrect dates on the screen.  The most significant bug reported was that one district had a problem with student services involving a very old computer.  This bug forced the district to use the back up system, which, luckily, was operational, causing no disruption of service.


Federal Operations

The Federal Housing Administration reported minor Y2K related problems in three "mission-critical" systems.  Two of these systems -- the Electronic Data Interchange (EDI), and Comprehensive Servicing and Monitoring System (CSMS) -- experienced problems which caused incorrect dates to appear on reports.  These errors did not affect any other content of the reports however, so the bug was minor.  The third system which experienced problems was the Single Family Insurance System (SFIS).  This error prevented users from terminating FDHA mortgages.  The results of these bugs were for the most part insignificant, and all were corrected promptly.

United States spy satellites transmitted unreadable data for three crucial days.  The bug was caused by a patch which was supposed to fix a Y2K bug, but caused the satellites to mangle data transmissions back to Earth.  The complications came at an uneasy time, as there were serious fears of terrorist attacks in the first few days of the millennium.  These satellites are used in prevention of terrorism.  Article, Article, Article

The Department of Housing and Urban Development experienced a bug with its Tenant Rental Assistance Certification System.  New records entered into the system had a default date of '01/01'19:0,' instead of '01/01/2000.'


Financial Sector

The Federal Reserve Bank of Chicago experienced Y2K related problems in transferring $700,000 in tax payments.  The bug was fixed and the payments were made the next day.

Bank credit card companies experienced a problem with credit card transaction verification software issues by CyberCash, Inc.  This problem created duplicate transactions for merchants that did not update their systems to the newer, Y2K compliant versions of the software.  Article, Article, Article, Article

One Chicago area bank had to interrupt electronic Medicare payments to some hospitals.  Insurance companies that process and pay Medicare claims had to send diskettes containing the processed claims to the bank via Federal Express or courier to keep payments on schedule.

500 members of the Golden 1 Credit Union found that, once year 2000 arrived, their ATM cards would not work at grocery stores and other locations which accept ATM cards as payments.  The cards were programmed to expire on December 31, 1999.  The cards were not supposed to have an expiration date, and the reason that such a small number of cards had the error is not known  Article

Online banking software used by thousands of Dutch bank customers had a millennium related bug which did not allow people to postdate their electronic payments.  The software was produced by Apple.  Article

A computer system belonging to the Hong Kong Futures Exchange failed as a result of a Y2K error.  The computer system controlling pricing for the Hang Seng Index options contracts was miscalculating the number of days between the trading day and the expiration date of many of the options traded.  Article


Law Enforcement

Y2K computer bug turns teen criminals into senior citizens.  Reports of sexual assault on an 83 year old woman by an 80 year old man, and two missing 'youths' of ages 83 and 84 were among the flawed reports given by the faulty system, which caused the system to read year 2000 as year 1900, and interpret the year of birth of the parties involved as their ages.  Article


Local Government

The Department of Motor Vehicles on St. Croix in the Virgin Islands had to be shut down temporarily because of a computer glitch which prevented correct registration of automobiles.

The State of Indiana's system for renewing driver's licenses gave some individuals licenses that did not expire for 5 years.  Indiana state law only allows renewals for four years. 

In Florida and Kentucky, the unemployment insurance benefit systems experienced a bug which prevented people from claiming earned income for the week ending on the first of January 2000.  Only two of the ten states which use this system experienced the problem.

The state of Nevada reported that the Y2K bug created problems for systems used by its Temporary Assistance for Needy Families program.  This bug affected only people who were born in the year 1990, and was corrected without a serious impact to service.  Another system used by the Child Welfare program system had a bug which caused the previous month's payment field to update incorrectly.  This problem was fixed quickly, once again, without a disruption in services.

One of Florida's State University System's Regional Data Centers reported a problem with its Computer Associate tape management system.  On-line access to the system should allow users to indicate that a tape is 'permanent,' meaning it should not be deleted.  The convention in use was to indicate that a tape was 'permanent' by setting its deletion date to '1999/365,' the 365th day of 1999.  This obviously created problems as we entered the year 2000, as tapes which were supposed to be permanent, were marked for deletion.

The Navajo Nation Law Enforcement Office reported that 7 of its 8 law enforcement servers had failed.  These servers contain law enforcement records.  Manual processes had to be implemented until the problems could be fixed.



In Malaysia there were reports of medical equipment failure.  Among the equipment that failed were defribillators and heart monitors  Article


Power and Utilities

Seven commercial nuclear reactors across the United States experienced minor glitches.  None of these posed a threat to safety.  The problems were with computer systems that are used to support physical plant access control and monitoring of operational data..  Details of this problem were not released.  Similar problems were experienced in nuclear power plants in Spain.  Article

A nuclear weapons plant in Tennessee experienced a bug in a computer which tracks the weight and type of nuclear material within the plant.  The bug at this plant was the only problem which did affect mission critical systems at Energy Department facilities across the nation.  Article, Article



Microsoft Internet Explorer and Microsoft Hotmail both displayed incorrect dates as a result of a programming command name 'Get Year.'  This command returned the year in two-digit format.  The result of this was that dates from the year 3900 were displayed.  Microsoft was aware of this bug, but did not implement a fix.  It asked programmers to change their code to use a new command 'Get Full Year.'  Any web pages written that still made use of the old function were subject to error.  Article

A large number of networked slot machines at racetracks were not operational for several hours.  This error was caused by an application which looks three days into the future.  Article, Article

Microsoft Visual Basic versions 3.0 and older, and Microsoft Access versions 2.0 and older are not Y2K compliant.  Programs written using these versions of Visual Basic may have problems not related to the code written in Visual Basic.  The non-compliance of the older versions of Access poses a big problem, because the newer versions simply do not work well with Windows 3.0, which is still being used by a significant number of companies.  Article

A customer at a New York State video rental store had a bill for $91,250, the cost of renting the movie 'The General's Daughter' for 100 years.  Article

Payroll software at Berlin's German Opera denied certain employees government mandated subsidies for families with children.  When year 2000 arrived, the computers date was 1900.  This caused a person born in 1995 to appear 95 years old, making the parents ineligible for the government subsidy.  Article



A software glitch resulting from an attempted last second fix done in haste causes massive delays in air transportation all over the east coast of the United States.  Article