Just as a for example, copy/paste this code into a file named "driveDemo.js":
var fso = new ActiveXObject("Scripting.FileSystemObject");
var driveLetters = "EFGHIJKLMNOP"; // or any other list of letter you want to check
var founddrives = "";
for ( var d = 0; d < driveLetters.length; ++d )
var letter = driveLetters.charAt(d);
if ( fso.DriveExists( letter ) )
founddrives += "Drive " + letter + ": found\n";
WScript.Echo( founddrives );
Then use windows explorer or MyComputer to find the folder where you saved that file.
Then simply double click on that file name.