Dim xSign As New XceedSigning
Dim vaSource As Variant
Dim vaSignature As Variant 

Set xSign.SigningMethod = New XceedRSASigningMethod 

vaSource = "This is the data to sign" 

On Error Resume Next 

  ' The following call to SetRandomKeyPair would, in the real world,
  ' be replaced by the assignment of a Private Key to the
  ' PrivateKey property. 

  Call xSign.SigningMethod.SetRandomKeyPair( 512, Empty )
  Call xSign.Sign(vaSource, True)

  vaSignature = xSign.SigningMethod.Signature 

  ' Do something with the signature 

  If Err.Number <> 0 Then
    Call MsgBox("Error 0x" & Hex(Err.Number) & " " & Err.Description) 
  Else
    Call MsgBox("Data signed successfully") 
  End If 

  If xSign.Verify(vaSource, True) Then
    Call MsgBox("Data verified successfully") 
  Else
    ' Should not happen 
    Call MsgBox("Verification of signature failed") 
  End If 

On Error Goto 0

Set xSign = Nothing