Private Declare Function GetUserName Lib "advapi32.dll" Alias "GetUserNameA" (ByVal lpBuffer As String, nSize As Long) As Long
Sub TestUser()
Dim lpBuff As String * 25, ret&, vUser$, vUser1$, vUser2$
ret = GetUserName(lpBuff, 25)
vUser = Environ("USERNAME")
MsgBox vUser, vbInformation, "Test1"
vUser1 = Application.UserName
MsgBox vUser1, vbInformation, "Test2"
vUser2 = Left(lpBuff, InStr(lpBuff, Chr(0)) - 1)
MsgBox vUser2, vbInformation, "Test3"
End Sub