Google takes desktop search software out of test tube

SAN FRANCISCO — Google Inc.’s free software for helping people find information stored on computer hard drives emerged from test mode Monday with an upgraded product.

The improvements in Google Desktop extend the software’s reach beyond material searched by the “beta,” version that’s been out since October as a free download.

With the expansion, the software now scours hard drives for information contained in Adobe Acrobat’s portable document format, or PDF, as well as music and video files. It also will scan content in more e-mail applications. The test version only sifted through e-mail in Microsoft Outlook.

The software still can’t handle the formats of hundreds of other applications that run on the Windows operating system. To address that shortcoming, Google is providing the software’s application program interface, or API, so outsiders can add more features to the package.

For instance, Google expects a plug-in to search for material stored in Apple Computer Inc.’s popular iTunes music library to be available soon.

Many of Google’s improvements match features already offered in the test versions of competing products from three of the company’s biggest search engine rivals — Yahoo Inc., Microsoft Corp. and Ask Jeeves Inc.

Mountain View-based Google is the first of that bunch to take its desktop search product out of the test tube, giving it an important stamp of credibility.