[Iska]

Например, так (не проверялось):

Скрытый текст

Код:

Option Explicit

Dim strSourceFile

Dim strContent

Dim objRegExp


strSourceFile = "E:\1.txt"

With WScript.CreateObject("Scripting.FileSystemObject")
	If .FileExists(strSourceFile) Then
		With .OpenTextFile(strSourceFile)
			strContent = .ReadAll()
			.Close
		End With
		
		Set objRegExp = WScript.CreateObject("VBScript.RegExp")
		
		With objRegExp
			.IgnoreCase = True
			.Global     = True
			.Pattern    = "мама"
		End With
		
		If objRegExp.Test(strContent) Then
			.CopyFile strSourceFile, .GetBaseName(strSourceFile) & ".bak" ,True
			
			Randomize Timer
			
			With .CreateTextFile(strSourceFile, True)
				.Write objRegExp.Replace(strContent, Array("Мама", "мыла", "раму")(Int(Rnd * 3)))
				.Close
			End With
		Else
			WScript.Echo "Pattern [" & objRegExp.Pattern & "] not found in content of source file [" & strSourceFile & "]."
			WScript.Quit 3
		End If
		
		Set objRegExp = Nothing
	Else
		WScript.Echo "Can't find source file [" & strSourceFile & "]."
		WScript.Quit 2
	End If
End With

WScript.Quit 0