But let it be known that customers may run into some pushback from Microsoft -- which recommends against these vendors' technologies because they violate Microsoft's licensing terms. According to Microsoft, IE is only licensed as an integrated part of the operating system (either originally or via updating earlier versions of IE) and IE is not licensed for use as a stand-alone feature.

However, Gartner notes that it has not heard of Microsoft taking formal legal action against vendors or customers of application or IE virtualization tools.

covers Microsoft, Windows, Operating Systems, Productivity Apps and Online Services for CIO.com. Follow Shane on Twitter . Follow everything from CIO.com on Twitter . Email Shane at soneill@cxo.com.