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Slideshow: Great Lost Software: 16 Gone But Not Forgotten

On Tuesday, startup Browsium announced the release of UniBrows, a lightweight browser add-on that enables existing Internet Explorer 6 applications to be run "as is" in IE8, on Windows XP, Windows Vista, and Windows 7 operating systems. UniBrows is transparent to end users. When they require an IE6 application, it simply loads in an IE8 tab.

Browsium is an enterprise software vendor which specializes in web application continuity. Behind the scenes, IT administrators use the UniBrows configuration manager to specify when the IE6 engine should load, on a per-application basis. They also can impose security restrictions, and allow legacy ActiveX and Java. These security settings are distributed to UniBrows clients using Group Policy Objects in Active Directory.

Who's still using IE6? According to Net Applications, as of February 2011, IE6 still accounted for 11% of all browsers, behind IE8 (35%), and Firefox (18%), but ahead of IE7 (8%) and Chrome (8%). Of course, IE6 use likely isn't by choice. "What people are clamoring for is to not run IE6, they're clamoring for a way to get off of it, and they're stuck on it," said Gary Schare, president and COO of Browsium in an interview.

Indeed, IE6 is outdated, unsupported, poses a security risk, and requires Windows XP. This not only prevents organizations from upgrading to Windows 7 -- Windows XP still commands twice the market share -- but also from installing a newer version of IE, or using applications such as Microsoft SharePoint 2010.

Many organizations, however, still rely on numerous, custom-developed applications that won't run on a modern browser. Others, meanwhile, bought software from the likes of PeopleSoft, SAP, Siebel, Hyperion, and niche, vertical-sector players, that's no longer supported.

"IE6 was the browser that had 95% market share at one point, so everyone built to it, and it had a lot of propriety interfaces. It was revolutionary in its day," said Schare, who was the IE project manager from the middle of IE6 through to IE8. He said that while UniBrows beta users hailed from all sectors, there's been a disproportionate level of interest from banking, pharmaceutical, and healthcare organizations, because they tend to use a relatively large number of custom-developed applications.

Interestingly, Browsium isn't pitching UniBrows merely as an IE6 salve, but also as a "Web Application Continuity" tool, able to freeze or restore IE8, IE7, or IE6 to its last-known working state. "New versions of Flash or Java tend to break very fragile Web apps," said Schare. "We let you freeze your Web app platform at whatever known-good state you need to make it work."

In the wake of Microsoft' s Monday release of IE9, he said that an IE9-comptible version of UniBrows should be released in a few weeks, after further compatibility testing.

Price-wise, for organizations with 5,000 to 50,000 PCs, UniBrows costs $5,000 annually, plus $5 per seat.

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