The problems with this approach are: - It can take a long time to extract the package, especially if you are looking at gigabyte applications. We are able to l

The problems with this approach are: - It can take a long time to extract the package, especially if you are looking at gigabyte applications. We are able to launch huge applications instantly because we avoid the extraction step. - Windows applications are typically hard-coded to read files from global locations like c:\windows\system32, side-by-side DLL locations, HKEY_LOCAL_MACHINE registry, font folders, services, etc. If you try to copy most applications to a single folder, they won't run. Some apps can be designed to run from a single folder, but this is the exception rather than the rule. - Ideally you don't want the application writing to other parts of the filesystem or registry because it might screw up other apps. We solved this by doing copy on write access to other parts of the PC and redirecting the writes to a local folder.