The keynote will begin at 9 a.m. PT, noon ET (5 p.m. GMT) on Wednesday, Jan. 21 at Microsoft's Redmond, Wash. headquarters.
Dubbing the event -- or at least the keynote -- as "Windows 10: The Next Chapter," Microsoft put up a page where people can access the webcast next week.
CEO Satya Nadella will participate in the keynote, Microsoft reiterated today, as will operating system chief Terry Myerson; one of his subordinates, Joe Belfiore, who leads Windows' design; and Phil Spencer, the head of the Xbox video gaming console division.
While the keynote will be webcast, other activities in the day-long event will not: those will be limited to the analysts and reporters who will be on-site.
The keynote and the day's other presentations are Windows 10's kick-off for 2015, which will be a busy year for the company. Microsoft plans to officially release the new operating system in the early fall, and will match that with a new version of Office, another of its biggest revenue generators.
"Both Windows and Office are due for a refresh this year," said Jan Dawson, principal analyst with Jackdaw Research, in an earlier interview. "We'll see those created in Nadella's image for the first time."
Next week, Microsoft will also probably launch the next iteration in Windows 10's preview, which will focus on the consumer-side features and use cases for the OS on PCs and tablets, and may include a new browser not named "Internet Explorer." According to reports, Microsoft will also soon begin rolling out a preview of Windows 10 for smartphones.