Handling OLE Errors
Private Sub LoginError(ProjectName As String, User As String, _
        &Password As String)

' This example shows handling of the OLE 
' exceptions thrown by OTA
' TDOLE_ILLEGALPASSWORD is a member of enumeration tagTDAPI_ERRORCODES

    On Error GoTo CheckError
    
     'tdc is a TDConnection object
    tdc.ConnectProject ProjectName, User, Password
    Exit Sub

CheckError:
    if (Err.Number - vbObjectError) = _
        TDAPIOLELib.TDOLE_ILLEGALPASSWORD Then
            LoginForm.Show 1
    Else
        MsgBox "Error: " & Err.Description, vbCritical
    End If
End Sub