VBScript

Convert a File's Character Encoding from UTF-8 to UFT-8-BOM

See more HTML-to-XML/Text Examples

To add a utf-8 BOM to a file is just a matter of prepending these 3 bytes to the file: 0xEF 0xBB 0xBF.

This may be difficult in some programming languages, or it may be trivial in either. Therefore, the Chilkat solution you see here might be helpful, or in a language such as C++, the Chilkat solution isn't really necessary because it's easy to do yourself.

VBScript

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

success = 0

' This example assumes the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

set charset = CreateObject("Chilkat.Charset")

charset.FromCharset = "utf-8"
charset.ToCharset = "bom-utf-8"

success = charset.ConvertFile("qa_data/txt/helloWorld.txt","qa_output/helloWorldBom.txt")
If (success <> 1) Then
    outFile.WriteLine(charset.LastErrorText)
    WScript.Quit
End If

outFile.WriteLine("Success.")

outFile.Close