SetAppPool.vbs

VBScript script Reference

A .vbs file contains a script in VBScript. The Windows Script Host runs the script. VBScript automates administration tasks on Windows and controls COM objects. The language is a light version of Visual Basic. Microsoft deprecated VBScript, and new scripts use PowerShell in its place.

A file extension is only a part of the file name. It does not give a guarantee about the format or the content of a file. But on Windows, the extension selects the program that opens the file.