Я нашел это через Google:http://www.mvps.org/access/api/api0008.htm

'******************** Code Start **************************
' This code was originally written by Dev Ashish.
' It is not to be altered or distributed,
' except as part of an application.
' You are free to use it in any application,
' provided the copyright notice is left unchanged.
'
' Code Courtesy of
' Dev Ashish
'
Private Declare Function apiGetUserName Lib "advapi32.dll" Alias _
    "GetUserNameA" (ByVal lpBuffer As String, nSize As Long) As Long

Function fOSUserName() As String
' Returns the network login name
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 = vbNullString
    End If
End Function
'******************** Code End **************************

Это лучший способ сделать это?