"From 2001 to 2006, Microsoft was very successful at getting organizations and independent software vendors (ISV) to write applications using features unique to IE6," Gartner analysts Michael Silver and David Mitchell Smith write in a new titled "Solving the IE6 Dilemma for Windows 7."

"Many homegrown, browser-based applications and ISV applications fail to run on IE8 or third-party browsers," the analysts continue. "Inventorying and remediating IE6 applications is extremely time-consuming, was not part of the promoted migration plans and tools from Microsoft, and is delaying Windows 7 migrations."

Businesses can't hold on to IE6 forever, though. Gartner offers several pieces of advice to those who need to move away from the 9-year-old browser. The best move is to fix or replace the affected applications so they can run on modern browsers that comply with Internet standards – but this is "potentially the most difficult solution," Gartner says.

Further options include running IE6 on a terminal server or hosted virtual desktop to offer at least temporary access. There's also Microsoft's Enterprise Desktop Virtualization [MED-V] package, but that can be quite expensive.