SystemErrorDescription - Convert an API error code to a string

Private Declare Function FormatMessage Lib "kernel32" Alias "FormatMessageA" _
    (ByVal dwFlags As Long, lpSource As Any, ByVal dwMessageId As Long, _
    ByVal dwLanguageId As Long, ByVal lpBuffer As String, ByVal nSize As Long, _
    Arguments As Long) As Long
Private Const FORMAT_MESSAGE_FROM_SYSTEM = &H1000

' Convert an API error number to a descriptive string
'
' If any error it returns an empty string, in which case
' the Err.LastDllError property can be use to retrieve
' extended error information

Function SystemErrorDescription(ByVal ErrCode As Long) As String
    Dim buffer As String * 1024
    Dim ret As Long
    ' return value is the length of the result message
    ret = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, 0, ErrCode, 0, buffer, _
        Len(buffer), 0)
    SystemErrorDescription = Left$(buffer, ret)
End Function