Yahoo has inked a deal to expand distribution of its Web search services on personal computers via a pact with software packaging firm Acresso Software, the companies said on Thursday. Acresso, which was recently spun off by entertainment media security company Macrovision, makes the widely used InstallShield, a technology used by software makers and corporate network administrators to install new PC programs.

Under the deal, Acresso plans to distribute to its customer base of more than 500 million computer users the Yahoo Toolbar -- an add-on to browsers that users can download, providing access to search and other Web navigation services from Yahoo.

Yahoo makes most of its money running ads alongside Web search and other services it offers.

Rival Google, the dominant Web search provider, has struck a succession of similar distribution deals for its own toolbar with partners ranging from software maker Adobe to PC maker Dell to social network MySpace.

Microsoft, the No. 3 in U.S. Web search after Yahoo, this week displaced Yahoo in a deal with Hewlett-Packard to distribute Microsoft search services on HP PCs.

Acresso counts among its customers major software makers such as Microsoft, SAS, BMC and IBM , as well as thousands of small software makers.

Details are at http://www.acresso.com/installshield/.