Updated

Google Inc. is offering a new tool that will automatically transfer information from one personal computer to another, but anyone wanting that convenience must authorize the Internet search leader to store the material for up to 30 days.

That compromise, sought as part of a free software upgrade to be released Thursday, might be more difficult to swallow now that the Bush administration is demanding to know what kind of information people have been trying to find through Google's search engine.

Google is fighting the Justice Department's subpoena in a federal court battle that's focusing more attention on the risks of personal information held by Internet companies being turned over to outside sources, including the government.

Yahoo Inc., Microsoft Corp. and Time Warner Inc.'s America Online already have surrendered some of the information requested by the Bush administration. All three companies have said their cooperation didn't violate users' privacy.

The ability to search a computer remotely is included in Google's latest upgrade to its software that scours hard drives for documents, e-mails, instant messages and an assortment of other information.

To enable the computer-to-computer search function, a user specifies what information should be indexed and then agrees to allow Google to transfer the material to its own storage system.

Google plans to encrypt all data transferred from users' hard drives and restrict access to just a handful of its employees. The company says it won't peruse any of the transferred information.

Once another computer participating in a user's personal network is turned on, Google automatically transfers the information so it's available to be searched.

Google intends to delete the information shortly after the electronic handoff, and will never retain anything from a user's hard drive for more than 30 days, said Sundar Pichai, director of product management.

Despite the privacy concerns likely to be raised, Google executives are confident the product will appeal to many people wanting a way to use a home computer to hunt data stored on an office computer, or vice versa.

"We think this will be a very useful tool, but you will have to give up some of your privacy," said Marissa Mayer, Google's vice president of search products and user experience. "For many of us, that trade off will make a lot of sense."

Besides empowering computer-to-computer searches, the improved software allows users to set up an array of mini-applications, sometimes called "widgets," to monitor topical information such as weather, stock quotes or news stories.

Google's revision also enables the widgets and other information to be shared with friends and co-workers, continuing the search engine's efforts to encourage more of the social interaction that has helped draw more traffic to its biggest Internet rival, Yahoo Inc., as well as other sites like MySpace.com.

Responding to complaints about its earlier versions of desktop search, Google's update provides password protection to make it more difficult for intruders to access the software.

The package, which can be downloaded at http://desktop.google.com, represents another significant building block in Google's attempt to create a computing platform to challenge Microsoft's Windows operating system, said Gartner analyst Allen Weiner.

The software will work only with Windows XP or Windows 2000 Service Pack 3.

"This is another way for Google to gain more control over the [computer] desktop and the consumer experience," Weiner said.

The computer-to-computer search feature could provide a stepping stone for Google to distribute a wide variety of digital media, including music and video, to mobile devices as well as other computers, said Greg Kelsey, a search engine analyst for the Kelsey Group.

Weiner agreed. "I think Google has a clear vision and realizes that access to anything from anywhere is going to be pretty valuable."

Google is rolling out its latest innovation against a backdrop of recent negative sentiment about the company. The backlash stems largely from Google's recent decision to censor its search results in China and investor concerns about a first-quarter profit that fell well below analyst estimates.