There are several ways to revise code to solve the y2k problem. A widely adopted technique is called windowing. It uses two-digit century date fields to identify the correct year: 29 is 2029; 80 is 1980; 10 is 2010, etc. (There is no agreed-upon standard regarding which years are assumed to be in which century.) It's cheaper than making the full four-digit revision. The IRS has retroactively forbidden this strategy and all others that cannot handle the four-digit year. It requires those agencies and firms that exchange data with its computers to adopt the four-digit approach.
Many organizations have already begun their code revision project. They cannot convert to the new standard, which was adopted in late 1997.
Question: How can the IRS enforce this? If it can't, what happens to the interoprtability of the computers? But if it can, how can the others conform?
* * * * * * *
The IRS said it will be contacting its external trading partners to inform them of the date by which data exchanges will be converted. The trading partners will be expected to certify that they will be ready to receive the data and that they will provide any related exchanges to the IRS as specified in the standard.