Вам нужно изменить имя функции с MD5 на другое.
Public Function BRGMOZ(ByVal sIn As String, Optional bB64 As Boolean = 0) As String
'Set a reference to mscorlib 4.0 64-bit
'Test with empty string input:
'Hex: d41d8cd98f00...etc
'Base-64: 1B2M2Y8Asg...etc
Dim oT As Object, oMD5 As Object
Dim TextToHash() As Byte
Dim bytes() As Byte
Set oT = CreateObject("System.Text.UTF8Encoding")
Set oMD5 = CreateObject("System.Security.Cryptography.MD5CryptoServiceProvider")
TextToHash = oT.Getbytes_4(sIn)
bytes = oMD5.ComputeHash_2((TextToHash))
If bB64 = True Then
BRGMOZ = ConvToBase64String(bytes)
Else
BRGMOZ = ConvToHexString(bytes)
End If
Set oT = Nothing
Set oMD5 = Nothing
End Function
А также добавить ссылку "mscorelib"
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РЕДАКТИРОВАТЬ: Витя уже ответил, извините.