Hewlett-Packard's delayed MediaSmart Server, based on Microsoft's Windows Home Server operating system, is making its way to retailers this month.

The new product for backing up and sharing photos, music, video, and documents over a home network is available for preorder through online retailers Amazon.com and Buy.com, as well as through the Web sites of Best Buy, Circuit City, and CompUSA, Microsoft and HP said in a statement released Sunday. Retailers expect to ship the hardware to customers later this month.

Windows Home Server is marketed as a consumer-friendly server that's an automatic back-up system for Windows XP- and Windows Vista-based home computers. In addition, the server is a central location for organizing digital documents and media, and includes a Windows Live Internet address from Microsoft for accessing the hardware from anywhere over the Web. Home Server also monitors the health and security status of networked PCs, and can stream media to Microsoft's Xbox 360 video game console, which could then be used to display the content on a digital TV.

The release of the HP MediaSmart Server gives Microsoft's new operating system a boost because HP is the world's largest computer maker. The new computer also is rolling out before the holiday season, which is the biggest shopping time of the year. HP plans to offer two versions of the product, a 500-Gbyte model for $599, and a 1-Tbyte model for $749. Processors from Advanced Micro Devices power the hardware.

Microsoft, HP, and other hardware manufacturers with Home Server-based products in the works are banking that the amount of digital content being created in homes will continue to grow, eventually making central storage devices a standard piece of equipment for many households.

HP won't be the first to ship a Home Server product in the United States. Velocity Micro is selling a 1-Tbyte device called the NetMagix HomeServer. Manufacturers planning to ship Home Server-based products early next year include Iomega and Life|ware.

In Europe, Tranquil PC is selling the Tranquil Harmony Home Server, including a 500-Gbyte and a 1-Tbyte model. Later this year, computer maker Medion plans to ship a 2-TByte Home Server product, and Fujitsu Siemens Computers plans to release the 1-Tbyte Scaleo Home Server.

Third-party software also is expected to make its way into the market. Diskeeper, for example, plans to release defragmentation software, and SageTV has released software for streaming media from Home Server to a PC or Apple Mac.

HP delayed the release of MediaSmart in August after Microsoft said it planned to release an update to the OS just two months after the software was released to manufacturers. While no one said the update was fixing flaws, HP decided to wait until the better version was available. HP had planned to start selling MediaSmart Home Server in late September or early October.