IT managers testing their Windows NT 4.0 systems for year-2000 compliance have yet another potential stumbling block to overcome: the PC's real-time clock (RTC).
Some Windows NT 4.0 applications, particularly those in time-sensitive usage such as manufacturing and financial systems, directly access PCs' RTCs, many of which are not year-2000 compliant.
In independent analysis, the InfoWorld Test Center found at least one application that accessed the RTC on a PC running NT 4.0. Using Right Time's CMOSView, a system utility, InfoWorld analysts accessed the RTC and found that the year value being read by NT 4.0 was "0000." In a subsequent test, Windows 95 read the same RTC on the same hardware as "2000."
This difference further confuses the testing that IT directors will have to perform and contradicts statements from Microsoft regarding access to the RTC.
"Consistent with programming best practices of not exposing any applications to the real-time clock directly, Windows [NT] 4.0 prohibits applications from directly accessing the real-time clock," according to Microsoft's Web site.
The problem could be severe because most RTCs are not compliant with year-2000 dates; they have only two digits in the year field instead of four digits.
Analysts said it is too soon to estimate how many applications will be affected.
"Many applications go directly to the RTC. The question is, do they have something in place to translate the date and time?" said Karen Moser, director of application development tools at the Aberdeen Group, a consultancy in Boston.
Applications that rely on precise time information -- financial, engineering, and manufacturing -- are frequently written to bypass time information from the operating system and to pull time information from the RTC. This practice ensures accurate information and can improve application performance.
Stuart Greenfield, a systems analyst for the State of Texas in Austin, said he is concerned about RTC access because Texas is building a Web-based tax filing application to run on NT 4.0. A key feature of the tax application will be date-stamping the returns.
Some PC hardware manufacturers have put their users on notice as to the potential for year-2000 problems arising from RTCs. Compaq acknowledged in a white paper that "any application that bypasses the OS and ROM BIOS to obtain data directly from the RTC may receive an incorrect date."
To resolve this problem, Microsoft suggested that companies redirect time-sensitive applications to a source other than the RTC.
"A good time source is typically a network time service [NT 4.0 resource kit and NT 5.0 built-in] pointed at a standard such as the Navy observatory time service, which continually supplies accurate time," said Jeff Price, Microsoft lead product manager for NT Server, in Redmond, Washington.
But applications that interpret noncompliant RTCs may be thrown off by this solution or even by buying a new PC.
"People are in a catch-22. If you get a server with a compliant RTC, then what do your applications do?" Greenfield said.
(Ephraim Schwartz contributed to this article.)