Private Declare Function apiGetUserName Lib "advapi32.dll" _
                         Alias "GetUserNameA" (ByVal lpBuffer As String, _
                                               nSize As Long) As Long
  
Function fOSUserName() As String
     Dim lngLen As Long, lngX As Long
     Dim strUserName As String
    
     strUserName = String$(254, 0)
     lngLen = 255
     lngX = apiGetUserName(strUserName, lngLen)
     If lngX <> 0 Then
        fOSUserName = Left$(strUserName, lngLen - 1)
       Else
        fOSUserName = ""
     End If
End Function

Function Ahoj() As String

  Ahoj = Application.UserName

End Function