[eluser]Unknown[/eluser]
I'm having the same problem, which is 'Notice: Undefined variable: user_name in c:\Inetpub\wwwroot\nssu2\main_admin.html on line 62'.
This are a few things that i have done to solve my problem, which it will work for you too.
First, on php.ini, you have to activate the ;error_reporting = E_ALL & ~E_NOTICE. Remove ; from error_reporting.
Second, i used echo "<srcipt type=text/javascript>location.href='main_admin.html'</srcipt>"; instead of header("Location: main_admin.html");
Example:
$_SESSION['AUTH'] = TRUE;
$_SESSION['USERNAME'] = $_POST['USERNAME'];
$_SESSION['CAMPUS'] = $_POST['CAMPUS'];
$_SESSION['LOGON'] = date("M d Y H:i

");
echo "<srcipt type=text/javascript>location.href='main_admin.html'</srcipt>";
ps: please replace srcipt to script. Cause it bcome a problem when i try to post this msg here.