IE 4.0 being double-checked

The week before Internet Explorer 4.0 is scheduled to go into its first public beta testing, Microsoft (MSFT) is carefully scrutinizing the browser for security holes.

The company is eager to avoid a repeat of last week when three potentially serious security holes were discovered in Internet Explorer 3.0 and 3.01. Although it is currently due out on the Internet on March 17, the release date for the first "platform preview" of Explorer 4.0 could slip slightly while the company runs last-minute security checks on the browser, according to sources.

Explorer 4.0 will tie Microsoft's browser more tightly with Windows 95 than the previous versions of the browser. With it, users will be able to seamlessly scan files and directories on their hard disks as though they were a series of Web pages and then jump out to public Internet sites, all without leaving Explorer.

But the close relationship between Microsoft's browser and operating system has raised concerns among some security experts. The university students who discovered the three security holes in Explorer last week said the glitches arose from Explorer 3.0's integration with certain Windows features such as Shortcuts. Netscape Communications' Navigator browser is not vulnerable in terms of these security holes.

The platform preview release of Explorer 4.0 will not be a fully functional version of the browser. It will not include "push" capabilities that allow users to automatically receive Internet content, according to a spokeswoman. The preview release will include Dynamic HTML, a technology for creating more interactive Web pages.

Microsoft has posted further information on Explorer 4.0 on its Web site.

On the eve of Internet World tomorrow, Brad Chase, Microsoft's vice president of marketing, will announce a "product initiative with strategic industry alliances." A company spokeswoman would not comment on the announcement.