Help! Session not being passed when URL is masked

[aBiz]

Hi,

I'm currently coding a wedding website for a friend, and all had been working great until now.

It includes an RSVP page that acts as a user registration, then allowing the user to login and access additional features of the site.

As I say, it's all been working fine, until I access the site via my friend's marked URL, when the session seems to stop being passed correctly.

The problem occurs thus:

If the user enters the correct password on the login page, the following code is run:

$_SESSION['logged'] = "agk8gjf38834j2";
$_SESSION['user'] = $_user_name;
header("location:" . $redirect_url);

This then redirects to a welcome page, where the following code runs:

ob_start();
session_start();
if($_SESSION['logged'] != 'agk8gjf38834j2')
{
header("location:" . $_login_file);
}

It is at this point, when using the masked URL, that I'm redirected back to the login page.  I've coded an echo to check the $_SESSION['logged'] variable, and sure enough it's blank when using the masked URL, but fine using the main URL.

If anyone has any ideas, or simple ways to get around this I would really appreciate you help.

Yours confusedly!
aBiz.  ???