NEW DELHI - Microsoft plans to nearly double its work force in India over the next four years, investing $1.7 billion and adding 3,000 jobs in a vote of confidence in one of the world's fastest-growing markets.

The investment would be among the largest an information technology company has made in this country of 1 billion people that Microsoft Corp. has long viewed as having huge potential in human capital and for sales.

Microsoft also said Wednesday that it plans to put aside funds for computer education and training, including adopting 100 schools for computer education, and support an Indian program to offer computers and training at 100,000 centers across the country.