During the transition from MS-DOS to Windows, the success of Microsoft's product Microsoft Office allowed the company to gain ground on application-software competitors, such as WordPerfect and Lotus 1-2-3. Novell, an owner of WordPerfect for a time, alleged that Microsoft used its inside knowledge of the DOS and Windows kernels and of undocumented Application Programming Interface features to make Office perform better than its competitors. Eventually, Microsoft Office became the dominant business suite, with a market share far exceeding that of its competitors. In March 1992, Microsoft released Windows 3.1 along with its first promotional campaign on TV; the software sold over three million copies in its first two months on the market. In October, Windows for Workgroups 3.1 was released with integrated networking abilities such as peer-to-peer file and printing sharing. In November, Microsoft released the first version of their popular database software Microsoft Access.