A Microsoft executive has confirmed that the leader of its search team is leaving the company.

In an internal memo viewed by IDG News Service, Microsoft's President of its Platforms and Services Division Kevin Johnson said that Christopher Payne is leaving Microsoft to form his own company. Published reports including one by The Wall Street Journal said as much last week, but Microsoft would not confirm his departure.

Johnson said in the memo -- dated Friday and sent Sunday night to Microsoft employees, sources said -- that he and Steven Sinofsky, senior vice president of Windows and Windows Live Engineering are searching for a successor for Payne.

"Christopher has been a tireless leader of our search R&D efforts over the last four years," Sinofsky wrote in his memo. "In that period, we've built a world-class search engine and a fantastic development team focused on this key business and product area for Microsoft. I thank Christopher for his leadership in this area, and wish him well in his future endeavors."

Johnson said Microsoft's online services business continues to be "crucial" to the company's future success, and the company is committed to "accelerating" its progress in this area.

"We need to drive hard on search, build our services platform to support users around the world, and deliver compelling user experiences," he wrote. "I appreciate your continued focus on the upcoming milestones and deliverables in our current search plan."

Microsoft could not be reached immediately for comment through its public relations firm on Monday.

Payne's bio remained online Monday, and Johnson's e-mail did not specify when the corporate vice president in charge of Windows Live Search would be leaving the company.

It also was not clear if Payne plans to leave Microsoft for his own reasons or if the company is terminating his employment. However, Microsoft's search and online business has not been faring well against Google since Microsoft unveiled a plan in November 2005 to rename its search engine Windows Live Search and develop other Web-based services under that moniker in an attempt to take more of the online advertising market. At the time, the company also announced a small-business hosted package called Office Live.

Revenue from Microsoft's online properties also remained relatively flat over the last fiscal year despite the company's increased investment to bolster this part of its business.

Before taking over Microsoft's Windows Live Search team, Payne was vice president of MSN.com, where he managed MSN Search, the MSN.com home page, MSN Autos, MSN Entertainment, MSNBC, Slate, and the MSN Channels properties.