"This design track (is) for a January shipment, but we're going to see what kind of feedback we get from users," Ballmer told reporters Thursday on the sidelines of the Seoul Digital Forum, a three-day gathering of leading figures in the technology industry.

"We've got still a lot of time, but we're going to work and make sure it's an absolutely high-quality product," he said.

Windows Vista is Microsoft's first major update to the company's flagship operating system since Windows XP was released in late 2001.

Microsoft said in March it would delay the release the consumer version of Vista until January 2007, missing the holiday sales season and throwing some PC makers and retailers into turmoil.

Ballmer also took the opportunity to clarify remarks he made Wednesday in Tokyo, suggesting they were misinterpreted in some news reports that said Vista could be delayed another few weeks.

"I said yesterday that Vista was on track to ship in the first part of next year ¡ª January as we had said," Ballmer said. "But I also emphasized that the most important thing is getting quality right.

"I was asked an unusual question and I think my answer was fine, but I don't think it was interpreted correctly," he said.