Many developers didn't design their Windows applications with multiuser Windows in mind. Therefore, these applications behave incorrectly during setup or, in some cases, when launched by more than one user concurrently during multiple terminal server sessions. Microsoft performed extensive compatibility testing on the most popular titles, and subsequently developed a set of application scripts that correct minor incompatibilities. In many cases, applications create files that you do not want to share globally but that you want each terminal session user to have.
The history, cookie, and temporary Internet files in Internet Explorer (IE) 3.0 are good examples. By default, IE stores these files in the shared %systemroot% directory. The Application Compatibility Script for IE 3.x changes these items' directories so that they point to the user's home directory, and thus are no longer shared.
Microsoft supplies Application Compatibility Scripts for each of the following applications: