[SOLVED] cannot show error message

[ironman32]

What I'm trying to do is show an error message if a field is empty.

Here is my code

<?php

$age = $_POST['age'];
$weight = $_POST['weight'];
$medical = $_POST['medical'];

if (empty ($_POST['age']) ){

header("Location: lose.php?msg=Invalid Login");
}
?>

 

I'm currently getting this error message

 

Warning: Cannot modify header information - headers already sent by (output started at /home/dontwork/public_html/workout3/lose2.php:2) in /home/dontwork/public_html/workout3/lose2.php on line 9

 

If anyone can help I would appreciate it.

[wildteen88]

The error is caused be cause on line 2 in lose2.php you have some form of output. Make sure you don't have anything before your opening php tag (<?php)

[schilly]

clear any space at the end of the php tag as well (after ?> at the end of the file)