попробуй эту функцию на VB переделать....

Private Function Crypt(ByVal Text As String, ByVal Key As String) As
String

Dim i As Long, KeyLen As Long, KeyPtr As Long, KeyChr As Integer, TextChr As Integer

KeyLen = Len(Key)
For i = 1 To Len(Text)
TextChr = Asc(Mid(Text, i, 1))
KeyChr = Asc(Mid(Key, KeyPtr + 1, 1))
Mid(Text, i, 1) = Chr(TextChr Xor KeyChr)
KeyPtr = ((KeyPtr + 1) Mod KeyLen)
Next i
Crypt = Text

End Function