Microsoft Corp. is expanding its local retail footprint — at least for the holidays. The Redmond, Wash., software giant said Monday that it will open stores in Natick and Braintree this fall.

The expansion follows Microsoft’s August opening of a store in The Shops at Prudential Center on Boylston Street — its first Boston store — and is part of its ongoing push into the retail marketplace to take on rival Apple Inc., which has 375 stores worldwide.