session_start help----

[strozzino]

this is the code that give me the error...
<?php

session_start();

if (($vadmin == "") AND ($vpassword == ""))
{
header("Location: login.php");
exit();
}

if (($vadmin == $admin) AND ($vpassword == $password)) {

//login succes
session_register("vadmin");
session_register("vpassword");

} else {

//failed to login
header("Location: login.php?error=1");
exit();
}

?>

the error is...

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at C:\PHP\sessiondata\profilax\asnforum-1.0\auth.php:2) in C:\PHP\sessiondata\profilax\asnforum-1.0\auth.php on line 16

Warning: Cannot modify header information - headers already sent by (output started at C:\PHP\sessiondata\profilax\asnforum-1.0\auth.php:2) in C:\PHP\sessiondata\profilax\asnforum-1.0\auth.php on line 20

please answer...

[planetsim]

if (($vadmin == "") AND ($vpassword == ""))

change to

if (empty($vadmin == "") && empty($vpassword == ""))

[alanzhao]

if (empty($vadmin == "") && empty($vpassword == ""))

it doesn't help. It's not the undefined varible problem.

My experience is header() can't not follow the session_start().