Microsoft Corp., Redmond, Wash., is staging a closed review of U.S. Windows advertising after pulling the assignment from Wieden & Kennedy, Portland, Ore. Spending could run into the tens of millions of dollars for next year's launch of Windows 2000. Microsoft has contacted a "small number'' of agencies including Anderson & Lembke, San Francisco, which will team up with parent McCann-Erickson Worldwide to pitch the business, said Jon Reingold, VP-corporate marketing. Anderson handles other Microsoft product and online advertising. Mr. Reingold said an earlier report that Anderson won the business was incorrect but added that the Anderson/McCann team "is definitely a leading candidate.'' Microsoft isn't interested in solicitations from other agencies, he said. Mr. Reingold said the review doesn't affect Wieden's brand assignment or Anderson's other Microsoft work. As part of a reorganization refocusing product groups on customer segments, Mr. Reingold said Microsoft wants to assign Windows to an agency that's close to business computer customers. Rob Schoeben, director of integrated marketing communications for the Business & Enterprise Division, is managing the review. This is Microsoft's first U.S. review since it hired Wieden and Anderson in 1994.