InstalledLocationVirtualization is the next big improvement to MSIX.
Although overlapping functionally with the PSF, the ILV is not a full replacement for the PSF’s FileRedirectionFixup or MFRFixup, as these will also be needed in a majority of repackaged apps. I expect a small number of apps may have conflict when used together right now, but over time, the PSF’s MFRFixup should become “ILV Aware” as we find and fix edge-cases where conflict occurs from using both techniques.
This paper is the result of research into this rather under-documented feature. It uncovers how the feature works, and what impacts it has on packages. The paper also relates this information to that of the Package Support Framework and discusses the advantages, and possible risks, of using both together.
The white paper also discusses the tools and techniques used in the research, which may be helpful for others looking to investigate how other kernel filter drivers operate..