After years of watching its partners use the Windows infrastructure for their own CRM products, Microsoft Corp. has decided to enter the game itself.

Announced this month and scheduled to ship in the second half of the year, Microsoft CRM is designed for small and midsize businesses. An offshoot of software developed by Great Plains Software, which Microsoft acquired last year, the package is designed to run on-premises or as a hosted application.

Notably, the tool will take advantage of Microsoft’s nascent .NET technology, a Web services platform that enables communication between various applications. In the case of CRM, .NET might coordinate information about customers stored separately in e-mail, contact management and sales force automation software.

But experts caution that .NET can’t completely solve some thorny problems. "It can unite Microsoft’s offerings, but what about companies that aren’t all-Microsoft?" said Mitch Kramer, an analyst with Patricia Seybold Group in Boston.

Those that use Netscape Mail or Lotus Notes, for example, would still have to find a way to extract customer data from those applications.

Microsoft already offers small businesses a service on its bCentral Web site for tracking sales leads, but that service requires all customer information to be stored on the Web site. By contrast, Microsoft CRM will take advantage of information already stored in a company’s own systems.

Another distinction is that bCentral is designed for companies with 25 or fewer employees, whereas Microsoft CRM is for companies with 25 to 100 employees, said Holly Holt, Microsoft product manager. Most companies of that size use a hodgepodge of homegrown applications, including spreadsheets, she said.