REDMOND, Wash. -- Microsoft reversed a decision to stop support for some older Windows operating systems, saying Monday some customers in developing countries were not aware of the change.

Support for Windows 98 and Windows 98 S.E. had been scheduled to expire Friday, and for Windows Millennium Edition on Dec. 31. Under Monday's decision, the software giant would maintain paid phone support for the operating systems and review security threats to determine whether it will provide customers with security patches through June 30, 2006.

"While we've done an excellent job communicating our life cycle policy for most of our products, we have found that we could use more time to communicate those guidelines in a handful of smaller markets," including Kazakhstan, the Ivory Coast and Slovenia, Microsoft spokesman Matt Pilla said.

About 20 percent of all Windows-based computers still run Windows 95 or 98, according to International Data Corp., a technology market research firm. Support for Windows 95 ended in 2001.

Since Oct. 15, 2002, Microsoft has offered seven years of support for its new products. Before that, it offered four.

First Published: January 13, 2004, 5:00 a.m.