The extraordinary defence of Microsoft in the face of bad news issued by the company itself turned a 7% share plunge overnight into a 1.5% gain and lent support to both major markets. The Dow Jones Industrial Average rose 51.83 points or 0.51% to 10,257.11. The Nasdaq Index slipped 5.60 points to 1,796.83. For the week, the Dow gained 0.7% while the Nasdaq tacked on 2.3%.